Double targeted constructs to affect tumor kill

ABSTRACT

The present technology is directed to compounds, compositions, medicaments, and methods related to the treatment of cancers expressing PSMA. The compounds are of Formulas I &amp; II 
     
       
         
         
             
             
         
       
     
     or pharmaceutically acceptable salts thereof. The present technology is especially well-suited for use in treating prostate cancer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to U.S. ProvisionalApplication No. 62/353,735, filed Jun. 23, 2016, the entirety of whichis hereby incorporated by reference for any and all purposes.

FIELD

The present technology is directed to compounds, compositions, andmethods related to the treatment of tumors that express prostatespecific membrane antigen (“PSMA”). The present technology isparticularly suited to treat prostate cancer.

SUMMARY

In an aspect, a compound according to Formula I is provided

or a pharmaceutically acceptable salt thereof, wherein X¹ is ¹²⁴I, ¹²⁵I,¹²⁷I, ¹³¹I, ²¹¹At, or Sn(R⁴)₃; R¹, R², and R³ are each independently H,methyl, benzyl, 4-methoxybenzyl, or tert-butyl; R⁴ is independently ateach occurrence an alkyl group; n is 1 or 2; and m is 0, 1, 2, or 3.

In an aspect, a compound of Formula II is provided

or a pharmaceutically acceptable salt thereof, wherein X² is ¹²⁴I, ¹²⁵I,¹²⁷I, ¹³¹I, ²¹¹At, or Sn(R⁸)₃; R⁵, R⁶, and R⁷ are each independently H,methyl, benzyl, 4-methoxybenzyl, or tert-butyl; R⁸ is independently ateach occurrence an alkyl group; W1 is a bond or —NH-alkylene-; and p is0, 1, 2, or 3.

In a related aspect, a composition is provided that includes a compoundof Formula I or II and a pharmaceutically acceptable carrier.

In a similar aspect, a pharmaceutical composition for treating prostatecancer is provided where the composition includes an effective amount ofa compound of Formula I or II.

In an aspect, a method is provided that includes administering acompound of Formula I or II to a subject suffering from prostate cancer.

In an aspect, a method of enhancing uptake of a therapeutic agent to atumor presenting prostate specific membrane antigen (“PSMA”) isprovided, where the method includes administering a first therapeuticagent comprising a PMSA targeting moiety and a human serum albuminbinding moiety to a subject with one or more prostate cancer tumors,where the human serum albumin binding moiety includes a radionuclide;detecting distribution of the first therapeutic agent in the subject;and modifying the first therapeutic agent to provide a secondtherapeutic agent.

DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1B provide the biodistribution in male nude mice bearing PSMA+LNCaP human tumor xenografts of ¹³¹I-RPS-001 at 24, 48, 72 and 96 h p.i.(FIG. 1A) and of a compound of the present technology ¹³¹I-RPS-005 at24, 48, 72 and 96 h p.i. (FIG. 1B).

FIG. 2 provides the biodistribution of ¹³¹I-RPS-020 at 1, 6, 12, 24 and48 h p.i. in male nude mice bearing PSMA+ LNCaP human tumor xenografts.

FIG. 3 provides the biodistribution of ¹³¹I-RPS-022 at 1, 6, 12, 24 and48 h p.i. in male nude mice bearing PSMA+ LNCaP human tumor xenografts.

FIG. 4 provides the biodistribution of ¹³¹I-RPS-027 at 1, 3, 6, 12, 18,24, 48, and 72 h p.i. in male nude mice bearing PSMA+ LNCaP human tumorxenografts.

FIG. 5 provides the results of μPET/CT imaging of LNCaP xenograft miceby PET/CT using ¹²⁴I-RPS-027 (7.4 MBq, 200 Ci).

FIGS. 6A-6C are plots of time-activity curves for blood (FIG. 6A), tumor(FIG. 6B), and kidney (FIG. 6C) derived from biodistribution data.

FIGS. 7A-7B provide the relative tumor-to-background ratios fortumor-to-blood (FIG. 7A) and tumor-to-kidney (FIG. 7B) furtherillustrating the effect of enhanced albumin-binding in tumor delivery ofthe respective compounds.

DETAILED DESCRIPTION

In various aspects, the present technology provides compounds andmethods for treatment of cancer expressing PSMA, and are particularlysuited to treat prostate cancer. The compounds provided herein can beformulated into pharmaceutical compositions and medicaments that areuseful in the disclosed methods. Also provided is the use of thecompounds in preparing pharmaceutical formulations and medicaments.

The following terms are used throughout as defined below.

As used herein and in the appended claims, singular articles such as “a”and “an” and “the” and similar referents in the context of describingthe elements (especially in the context of the following claims) are tobe construed to cover both the singular and the plural, unless otherwiseindicated herein or clearly contradicted by context. Recitation ofranges of values herein are merely intended to serve as a shorthandmethod of referring individually to each separate value falling withinthe range, unless otherwise indicated herein, and each separate value isincorporated into the specification as if it were individually recitedherein. All methods described herein can be performed in any suitableorder unless otherwise indicated herein or otherwise clearlycontradicted by context. The use of any and all examples, or exemplarylanguage (e.g., “such as”) provided herein, is intended merely to betterilluminate the embodiments and does not pose a limitation on the scopeof the claims unless otherwise stated. No language in the specificationshould be construed as indicating any non-claimed element as essential.

As used herein, “about” will be understood by persons of ordinary skillin the art and will vary to some extent depending upon the context inwhich it is used. If there are uses of the term which are not clear topersons of ordinary skill in the art, given the context in which it isused, “about” will mean up to plus or minus 10% of the particular term.

Generally, reference to a certain element such as hydrogen or H is meantto include all isotopes of that element. For example, if an R group isdefined to include hydrogen or H, it also includes deuterium andtritium. Compounds comprising radioisotopes such as tritium, ¹⁴C, ³²P,and ³⁵S are thus within the scope of the present technology. Proceduresfor inserting such labels into the compounds of the present technologywill be readily apparent to those skilled in the art based on thedisclosure herein.

In general, “substituted” refers to an organic group as defined below(e.g., an alkyl group) in which one or more bonds to a hydrogen atomcontained therein are replaced by a bond to non-hydrogen or non-carbonatoms. Substituted groups also include groups in which one or more bondsto a carbon(s) or hydrogen(s) atom are replaced by one or more bonds,including double or triple bonds, to a heteroatom. Thus, a substitutedgroup is substituted with one or more substituents, unless otherwisespecified. In some embodiments, a substituted group is substituted with1, 2, 3, 4, 5, or 6 substituents. Examples of substituent groupsinclude: halogens (i.e., F, Cl, Br, and I); hydroxyls; alkoxy, alkenoxy,aryloxy, aralkyloxy, heterocyclyl, heterocyclylalkyl, heterocyclyloxy,and heterocyclylalkoxy groups; carbonyls (oxo); carboxylates; esters;urethanes; oximes; hydroxylamines; alkoxyamines; aralkoxyamines; thiols;sulfides; sulfoxides; sulfones; sulfonyls; pentafluorosulfanyl (i.e.,SFs), sulfonamides; amines; N-oxides; hydrazines; hydrazides;hydrazones; azides; amides; ureas; amidines; guanidines; enamines;imides; isocyanates; isothiocyanates; cyanates; thiocyanates; imines;nitro groups; nitriles (i.e., CN); and the like.

Substituted ring groups such as substituted cycloalkyl, aryl,heterocyclyl and heteroaryl groups also include rings and ring systemsin which a bond to a hydrogen atom is replaced with a bond to a carbonatom. Therefore, substituted cycloalkyl, aryl, heterocyclyl andheteroaryl groups may also be substituted with substituted orunsubstituted alkyl, alkenyl, and alkynyl groups as defined below.

Alkyl groups include straight chain and branched chain alkyl groupshaving from 1 to 12 carbon atoms, and typically from 1 to 10 carbons or,in some embodiments, from 1 to 8, 1 to 6, or 1 to 4 carbon atoms. Alkylgroups may be substituted or unsubstituted. Examples of straight chainalkyl groups include groups such as methyl, ethyl, n-propyl, n-butyl,n-pentyl, n-hexyl, n-heptyl, and n-octyl groups. Examples of branchedalkyl groups include, but are not limited to, isopropyl, iso-butyl,sec-butyl, tert-butyl, neopentyl, isopentyl, and 2,2-dimethylpropylgroups. Representative substituted alkyl groups may be substituted oneor more times with substituents such as those listed above, and includewithout limitation haloalkyl (e.g., trifluoromethyl), hydroxyalkyl,thioalkyl, aminoalkyl, alkylaminoalkyl, dialkylaminoalkyl, alkoxyalkyl,carboxyalkyl, and the like.

Cycloalkyl groups include mono-, bi- or tricyclic alkyl groups havingfrom 3 to 12 carbon atoms in the ring(s), or, in some embodiments, 3 to10, 3 to 8, or 3 to 4, 5, or 6 carbon atoms. Cycloalkyl groups may besubstituted or unsubstituted. Exemplary monocyclic cycloalkyl groupsinclude, but not limited to, cyclopropyl, cyclobutyl, cyclopentyl,cyclohexyl, cycloheptyl, and cyclooctyl groups. In some embodiments, thecycloalkyl group has 3 to 8 ring members, whereas in other embodimentsthe number of ring carbon atoms range from 3 to 5, 3 to 6, or 3 to 7.Bi- and tricyclic ring systems include both bridged cycloalkyl groupsand fused rings, such as, but not limited to, bicyclo[2.1.1]hexane,adamantyl, decalinyl, and the like. Substituted cycloalkyl groups may besubstituted one or more times with, non-hydrogen and non-carbon groupsas defined above. However, substituted cycloalkyl groups also includerings that are substituted with straight or branched chain alkyl groupsas defined above. Representative substituted cycloalkyl groups may bemono-substituted or substituted more than once, such as, but not limitedto, 2,2-, 2,3-, 2,4-2,5- or 2,6-disubstituted cyclohexyl groups, whichmay be substituted with substituents such as those listed above.

Cycloalkylalkyl groups are alkyl groups as defined above in which ahydrogen or carbon bond of an alkyl group is replaced with a bond to acycloalkyl group as defined above. Cycloalkylalkyl groups may besubstituted or unsubstituted. In some embodiments, cycloalkylalkylgroups have from 4 to 16 carbon atoms, 4 to 12 carbon atoms, andtypically 4 to 10 carbon atoms. Substituted cycloalkylalkyl groups maybe substituted at the alkyl, the cycloalkyl or both the alkyl andcycloalkyl portions of the group. Representative substitutedcycloalkylalkyl groups may be mono-substituted or substituted more thanonce, such as, but not limited to, mono-, di- or tri-substituted withsubstituents such as those listed above.

Alkenyl groups include straight and branched chain alkyl groups asdefined above, except that at least one double bond exists between twocarbon atoms. Alkenyl groups may be substituted or unsubstituted.Alkenyl groups have from 2 to 12 carbon atoms, and typically from 2 to10 carbons or, in some embodiments, from 2 to 8, 2 to 6, or 2 to 4carbon atoms. In some embodiments, the alkenyl group has one, two, orthree carbon-carbon double bonds. Examples include, but are not limitedto vinyl,

allyl, —CH═CH(CH₃), —CH═C(CH₃)₂, —C(CH₃)═CH₂, —C(CH₃)═CH(CH₃),—C(CH₂CH₃)═CH₂, among others. Representative substituted alkenyl groupsmay be mono-substituted or substituted more than once, such as, but notlimited to, mono-, di- or tri-substituted with substituents such asthose listed above.

Cycloalkenyl groups include cycloalkyl groups as defined above, havingat least one double bond between two carbon atoms. Cycloalkenyl groupsmay be substituted or unsubstituted. In some embodiments thecycloalkenyl group may have one, two or three double bonds but does notinclude aromatic compounds. Cycloalkenyl groups have from 4 to 14 carbonatoms, or, in some embodiments, 5 to 14 carbon atoms, 5 to 10 carbonatoms, or even 5, 6, 7, or 8 carbon atoms. Examples of cycloalkenylgroups include cyclohexenyl, cyclopentenyl, cyclohexadienyl,cyclobutadienyl, and cyclopentadienyl.

Cycloalkenylalkyl groups are alkyl groups as defined above in which ahydrogen or carbon bond of the alkyl group is replaced with a bond to acycloalkenyl group as defined above.

Cycloalkenylalkyl groups may be substituted or unsubstituted.Substituted cycloalkenylalkyl groups may be substituted at the alkyl,the cycloalkenyl or both the alkyl and cycloalkenyl portions of thegroup. Representative substituted cycloalkenylalkyl groups may besubstituted one or more times with substituents such as those listedabove.

Alkynyl groups include straight and branched chain alkyl groups asdefined above, except that at least one triple bond exists between twocarbon atoms. Alkynyl groups may be substituted or unsubstituted.Alkynyl groups have from 2 to 12 carbon atoms, and typically from 2 to10 carbons or, in some embodiments, from 2 to 8, 2 to 6, or 2 to 4carbon atoms. In some embodiments, the alkynyl group has one, two, orthree carbon-carbon triple bonds. Examples include, but are not limitedto —C≡CH, —C≡CCH₃, —CH₂C≡CCH₃, —C≡CCH₂CH(CH₂CH₃)₂, among others.Representative substituted alkynyl groups may be mono-substituted orsubstituted more than once, such as, but not limited to, mono-, di- ortri-substituted with substituents such as those listed above.

Aryl groups are cyclic aromatic hydrocarbons that do not containheteroatoms. Aryl groups may be substituted or unsubstituted. Arylgroups herein include monocyclic, bicyclic and tricyclic ring systems.Thus, aryl groups include, but are not limited to, phenyl, azulenyl,heptalenyl, biphenyl, fluorenyl, phenanthrenyl, anthracenyl, indenyl,indanyl, pentalenyl, and naphthyl groups. In some embodiments, arylgroups contain 6-14 carbons, and in others from 6 to 12 or even 6-10carbon atoms in the ring portions of the groups. In some embodiments,the aryl groups are phenyl or naphthyl. The phrase “aryl groups”includes groups containing fused rings, such as fused aromatic-aliphaticring systems (e.g., indanyl, tetrahydronaphthyl, and the like).Representative substituted aryl groups may be mono-substituted orsubstituted more than once. For example, monosubstituted aryl groupsinclude, but are not limited to, 2-, 3-, 4-, 5-, or 6-substituted phenylor naphthyl groups, which may be substituted with substituents such asthose listed above.

Aralkyl groups are alkyl groups as defined above in which a hydrogen orcarbon bond of an alkyl group is replaced with a bond to an aryl groupas defined above. Aralkyl groups may be substituted or unsubstituted. Insome embodiments, aralkyl groups contain 7 to 16 carbon atoms, 7 to 14carbon atoms, or 7 to 10 carbon atoms. Substituted aralkyl groups may besubstituted at the alkyl, the aryl or both the alkyl and aryl portionsof the group. Representative aralkyl groups include but are not limitedto benzyl and phenethyl groups and fused (cycloalkylaryl)alkyl groupssuch as 4-indanylethyl. Representative substituted aralkyl groups may besubstituted one or more times with substituents such as those listedabove.

Heterocyclyl groups include aromatic (also referred to as heteroaryl)and non-aromatic ring compounds containing 3 or more ring members, ofwhich one or more is a heteroatom such as, but not limited to, N, O, andS. Heterocyclyl groups may be substituted or unsubstituted. In someembodiments, the heterocyclyl group contains 1, 2, 3 or 4 heteroatoms.In some embodiments, heterocyclyl groups include mono-, bi- andtricyclic rings having 3 to 16 ring members, whereas other such groupshave 3 to 6, 3 to 10, 3 to 12, or 3 to 14 ring members.

Heterocyclyl groups encompass aromatic, partially unsaturated andsaturated ring systems, such as, for example, imidazolyl, imidazolinyland imidazolidinyl groups. The phrase “heterocyclyl group” includesfused ring species including those comprising fused aromatic andnon-aromatic groups, such as, for example, benzotriazolyl,2,3-dihydrobenzo[1,4]dioxinyl, and benzo[1,3]dioxolyl. The phrase alsoincludes bridged polycyclic ring systems containing a heteroatom suchas, but not limited to, quinuclidyl. Heterocyclyl groups include, butare not limited to, aziridinyl, azetidinyl, pyrrolidinyl,imidazolidinyl, pyrazolidinyl, thiazolidinyl, tetrahydrothiophenyl,tetrahydrofuranyl, dioxolyl, furanyl, thiophenyl, pyrrolyl, pyrrolinyl,imidazolyl, imidazolinyl, pyrazolyl, pyrazolinyl, triazolyl, tetrazolyl,oxazolyl, isoxazolyl, thiazolyl, thiazolinyl, isothiazolyl,thiadiazolyl, oxadiazolyl, piperidyl, piperazinyl, morpholinyl,thiomorpholinyl, tetrahydropyranyl, tetrahydrothiopyranyl, oxathiane,dioxyl, dithianyl, pyranyl, pyridyl, pyrimidinyl, pyridazinyl,pyrazinyl, triazinyl, dihydropyridyl, dihydrodithiinyl,dihydrodithionyl, homopiperazinyl, quinuclidyl, indolyl, indolinyl,isoindolyl, azaindolyl (pyrrolopyridyl), indazolyl, indolizinyl,benzotriazolyl, benzimidazolyl, benzofuranyl, benzothiophenyl,benzthiazolyl, benzoxadiazolyl, benzoxazinyl, benzodithiinyl,benzoxathiinyl, benzothiazinyl, benzoxazolyl, benzothiazolyl,benzothiadiazolyl, benzo[1,3]dioxolyl, pyrazolopyridyl, imidazopyridyl(azabenzimidazolyl), triazolopyridyl, isoxazolopyridyl, purinyl,xanthinyl, adeninyl, guaninyl, quinolinyl, isoquinolinyl, quinolizinyl,quinoxalinyl, quinazolinyl, cinnolinyl, phthalazinyl, naphthyridinyl,pteridinyl, thianaphthyl, dihydrobenzothiazinyl, dihydrobenzofuranyl,dihydroindolyl, dihydrobenzodioxinyl, tetrahydroindolyl,tetrahydroindazolyl, tetrahydrobenzimidazolyl, tetrahydrobenzotriazolyl,tetrahydropyrrolopyridyl, tetrahydropyrazolopyridyl,tetrahydroimidazopyridyl, tetrahydrotriazolopyridyl, andtetrahydroquinolinyl groups. Representative substituted heterocyclylgroups may be mono-substituted or substituted more than once, such as,but not limited to, pyridyl or morpholinyl groups, which are 2-, 3-, 4-,5-, or 6-substituted, or disubstituted with various substituents such asthose listed above.

Heteroaryl groups are aromatic ring compounds containing 5 or more ringmembers, of which, one or more is a heteroatom such as, but not limitedto, N, O, and S. Heteroaryl groups may be substituted or unsubstituted.Heteroaryl groups include, but are not limited to, groups such aspyrrolyl, pyrazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl,thiazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, thiophenyl,benzothiophenyl, furanyl, benzofuranyl, indolyl, azaindolyl(pyrrolopyridinyl), indazolyl, benzimidazolyl, imidazopyridinyl(azabenzimidazolyl), pyrazolopyridinyl, triazolopyridinyl,benzotriazolyl, benzoxazolyl, benzothiazolyl, benzothiadiazolyl,imidazopyridinyl, isoxazolopyridinyl, thianaphthyl, purinyl, xanthinyl,adeninyl, guaninyl, quinolinyl, isoquinolinyl, tetrahydroquinolinyl,quinoxalinyl, and quinazolinyl groups. Heteroaryl groups include fusedring compounds in which all rings are aromatic such as indolyl groupsand include fused ring compounds in which only one of the rings isaromatic, such as 2,3-dihydro indolyl groups. The phrase “heteroarylgroups” includes fused ring compounds. Representative substitutedheteroaryl groups may be substituted one or more times with varioussubstituents such as those listed above.

Heterocyclylalkyl groups are alkyl groups as defined above in which ahydrogen or carbon bond of an alkyl group is replaced with a bond to aheterocyclyl group as defined above. Heterocyclylalkyl groups may besubstituted or unsubstituted. Substituted heterocyclylalkyl groups maybe substituted at the alkyl, the heterocyclyl or both the alkyl andheterocyclyl portions of the group. Representative heterocyclyl alkylgroups include, but are not limited to, morpholin-4-yl-ethyl,furan-2-yl-methyl, imidazol-4-yl-methyl, pyridin-3-yl-methyl,tetrahydrofuran-2-yl-ethyl, and indol-2-yl-propyl. Representativesubstituted heterocyclylalkyl groups may be substituted one or moretimes with substituents such as those listed above.

Heteroaralkyl groups are alkyl groups as defined above in which ahydrogen or carbon bond of an alkyl group is replaced with a bond to aheteroaryl group as defined above. Heteroaralkyl groups may besubstituted or unsubstituted. Substituted heteroaralkyl groups may besubstituted at the alkyl, the heteroaryl or both the alkyl andheteroaryl portions of the group. Representative substitutedheteroaralkyl groups may be substituted one or more times withsubstituents such as those listed above.

Groups described herein having two or more points of attachment (i.e.,divalent, trivalent, or polyvalent) within the compound of the presenttechnology are designated by use of the suffix, “ene.” For example,divalent alkyl groups are alkylene groups, divalent aryl groups arearylene groups, divalent heteroaryl groups are divalent heteroarylenegroups, and so forth. Substituted groups having a single point ofattachment to the compound of the present technology are not referred tousing the “ene” designation. Thus, e.g., chloroethyl is not referred toherein as chloroethylene.

Alkoxy groups are hydroxyl groups (—OH) in which the bond to thehydrogen atom is replaced by a bond to a carbon atom of a substituted orunsubstituted alkyl group as defined above. Alkoxy groups may besubstituted or unsubstituted. Examples of linear alkoxy groups includebut are not limited to methoxy, ethoxy, propoxy, butoxy, pentoxy,hexoxy, and the like. Examples of branched alkoxy groups include but arenot limited to isopropoxy, sec-butoxy, tert-butoxy, isopentoxy,isohexoxy, and the like. Examples of cycloalkoxy groups include but arenot limited to cyclopropyloxy, cyclobutyloxy, cyclopentyloxy,cyclohexyloxy, and the like. Representative substituted alkoxy groupsmay be substituted one or more times with substituents such as thoselisted above.

The terms “alkanoyl” and “alkanoyloxy” as used herein can refer,respectively, to —C(O)-alkyl groups and —O—C(O)-alkyl groups, eachcontaining 2-5 carbon atoms. Similarly, “aryloyl” and “aryloyloxy” referto —C(O)-aryl groups and —O—C(O)-aryl groups.

The terms “aryloxy” and “arylalkoxy” refer to, respectively, asubstituted or unsubstituted aryl group bonded to an oxygen atom and asubstituted or unsubstituted aralkyl group bonded to the oxygen atom atthe alkyl. Examples include but are not limited to phenoxy, naphthyloxy,and benzyloxy. Representative substituted aryloxy and arylalkoxy groupsmay be substituted one or more times with substituents such as thoselisted above.

The term “carboxylate” as used herein refers to a —C(O)OH group. Theterm “protected carboxylate” refers to —C(O)O-G groups, where G is acarboxylate protecting group.

Carboxylate protecting groups are well known to one of ordinary skill inthe art. An extensive list of protecting groups for the carboxylategroup functionality may be found in Protective Groups in OrganicSynthesis, Greene, T.W.; Wuts, P. G. M., John Wiley & Sons, New York,N.Y., (3rd Edition, 1999) which can be added or removed using theprocedures set forth therein and which is hereby incorporated byreference in its entirety and for any and all purposes as if fully setforth herein.

The term “ester” as used herein refers to —COOR⁷⁰. R⁷⁰ is a substitutedor unsubstituted alkyl, cycloalkyl, alkenyl, alkynyl, aryl, aralkyl,heterocyclylalkyl or heterocyclyl group as defined herein.

The term “amide” (or “amido”) includes C- and N-amide groups, i.e.,—C(O)NR⁷¹R⁷², and —NR⁷¹C(O)R⁷² groups, respectively. R⁷¹ and R⁷² areindependently hydrogen, or a substituted or unsubstituted alkyl,alkenyl, alkynyl, cycloalkyl, aryl, aralkyl, heterocyclylalkyl orheterocyclyl group as defined herein. Amido groups therefore include butare not limited to carbamoyl groups (—C(O)NH₂) and formamide groups(—NHC(O)H). In some embodiments, the amide is —NR⁷¹C(O)—(C₁₋₅ alkyl) andthe group is termed “carbonylamino,” and in others the amide is—NHC(O)-alkyl and the group is termed “alkanoylamino.”

The term “nitrile” or “cyano” as used herein refers to the —CN group.

Urethane groups include N- and O-urethane groups, i.e., —NR⁷³C(O)OR⁷⁴and —OC(O)NR⁷³R⁷⁴ groups, respectively. R⁷³ and R⁷⁴ are independently asubstituted or unsubstituted alkyl, alkenyl, alkynyl, cycloalkyl, aryl,aralkyl, heterocyclylalkyl, or heterocyclyl group as defined herein. R⁷³may also be H.

The term “amine” (or “amino”) as used herein refers to —NR⁷⁵R⁷⁶ groups,wherein R⁷⁵ and R⁷⁶ are independently hydrogen, or a substituted orunsubstituted alkyl, alkenyl, alkynyl, cycloalkyl, aryl, aralkyl,heterocyclylalkyl or heterocyclyl group as defined herein. In someembodiments, the amine is alkylamino, dialkylamino, arylamino, oralkylarylamino. In other embodiments, the amine is NH₂, methylamino,dimethylamino, ethylamino, diethylamino, propylamino, isopropylamino,phenylamino, or benzylamino.

The term “sulfonamido” includes S- and N-sulfonamide groups, i.e.,—SO₂NR⁷⁸R⁷⁹ and —NR⁷⁸SO₂R⁷⁹ groups, respectively. R⁷⁸ and R⁷⁹ areindependently hydrogen, or a substituted or unsubstituted alkyl,alkenyl, alkynyl, cycloalkyl, aryl, aralkyl, heterocyclylalkyl, orheterocyclyl group as defined herein. Sulfonamido groups thereforeinclude but are not limited to sulfamoyl groups (—SO₂NH₂). In someembodiments herein, the sulfonamido is —NHSO₂-alkyl and is referred toas the “alkylsulfonylamino” group.

The term “thiol” refers to —SH groups, while “sulfides” include —SR⁸⁰groups, “sulfoxides” include —S(O)R⁸¹ groups, “sulfones” include —SO₂R⁸²groups, and “sulfonyls” include —SO₂OR⁸³. R⁸⁰, R⁸¹, R⁸², and R⁸³ areeach independently a substituted or unsubstituted alkyl, cycloalkyl,alkenyl, alkynyl, aryl aralkyl, heterocyclyl or heterocyclylalkyl groupas defined herein. In some embodiments the sulfide is an alkylthiogroup, —S-alkyl.

The term “urea” refers to —NR⁸⁴—C(O)—NR⁸⁵R⁸⁶ groups. R⁸⁴, R⁸⁵, and R⁸⁶groups are independently hydrogen, or a substituted or unsubstitutedalkyl, alkenyl, alkynyl, cycloalkyl, aryl, aralkyl, heterocyclyl, orheterocyclylalkyl group as defined herein.

The term “amidine” refers to —C(NR⁸⁷)NR⁸⁸R⁸⁹ and —NR⁸⁷C(NR⁸⁸)R⁸⁹,wherein R⁸⁷, R⁸⁸, and R⁸⁹ are each independently hydrogen, or asubstituted or unsubstituted alkyl, cycloalkyl, alkenyl, alkynyl, arylaralkyl, heterocyclyl or heterocyclylalkyl group as defined herein.

The term “guanidine” refers to —NR⁹⁰C(NR⁹¹)NR⁹²R⁹³, wherein R⁹⁰, R⁹¹,R⁹² and R⁹³ are each independently hydrogen, or a substituted orunsubstituted alkyl, cycloalkyl, alkenyl, alkynyl, aryl aralkyl,heterocyclyl or heterocyclylalkyl group as defined herein.

The term “enamine” refers to —C(R⁹⁴)═C(R⁹⁵)NR⁹⁶R⁹⁷ and—NR⁹⁴C(R⁹⁵)═C(R⁹⁶)R⁹⁷, wherein R⁹⁴, R⁹⁵, R⁹⁶ and R⁹⁷ are eachindependently hydrogen, a substituted or unsubstituted alkyl,cycloalkyl, alkenyl, alkynyl, aryl aralkyl, heterocyclyl orheterocyclylalkyl group as defined herein.

The term “halogen” or “halo” as used herein refers to bromine, chlorine,fluorine, or iodine. In some embodiments, the halogen is fluorine. Inother embodiments, the halogen is chlorine or bromine.

The term “hydroxyl” as used herein can refer to —OH or its ionized form,—O⁻. A “hydroxyalkyl” group is a hydroxyl-substituted alkyl group, suchas HO—CH₂—.

As will be understood by one skilled in the art, for any and allpurposes, particularly in terms of providing a written description, allranges disclosed herein also encompass any and all possible subrangesand combinations of subranges thereof. Any listed range can be easilyrecognized as sufficiently describing and enabling the same range beingbroken down into at least equal halves, thirds, quarters, fifths,tenths, etc. As a non-limiting example, each range discussed herein canbe readily broken down into a lower third, middle third and upper third,etc. As will also be understood by one skilled in the art all languagesuch as “up to,” “at least,” “greater than,” “less than,” and the likeinclude the number recited and refer to ranges which can be subsequentlybroken down into subranges as discussed above. Finally, as will beunderstood by one skilled in the art, a range includes each individualmember. Thus, for example, a group having 1-3 atoms refers to groupshaving 1, 2, or 3 atoms. Similarly, a group having 1-5 atoms refers togroups having 1, 2, 3, 4, or 5 atoms, and so forth.

Pharmaceutically acceptable salts of compounds described herein arewithin the scope of the present technology and include acid or baseaddition salts which retain the desired pharmacological activity and isnot biologically undesirable (e.g., the salt is not unduly toxic,allergenic, or irritating, and is bioavailable). When the compound ofthe present technology has a basic group, such as, for example, an aminogroup, pharmaceutically acceptable salts can be formed with inorganicacids (such as hydrochloric acid, hydroboric acid, nitric acid, sulfuricacid, and phosphoric acid), organic acids (e.g. alginate, formic acid,acetic acid, trifluoroacetic acid, benzoic acid, gluconic acid, fumaricacid, oxalic acid, tartaric acid, lactic acid, maleic acid, citric acid,succinic acid, malic acid, methanesulfonic acid, benzenesulfonic acid,naphthalene sulfonic acid, and p-toluenesulfonic acid) or acidic aminoacids (such as aspartic acid and glutamic acid). When the compound ofthe present technology has an acidic group, such as for example, acarboxylic acid group, it can form salts with metals, such as alkali andearth alkali metals (e.g. Na⁺, Li⁺, K⁺, Ca²⁺, Mg²⁺, Zn²⁺), ammonia ororganic amines (e.g. dicyclohexylamine, trimethylamine, triethylamine,pyridine, picoline, ethanolamine, diethanolamine, triethanolamine) orbasic amino acids (e.g. arginine, lysine and ornithine). Such salts canbe prepared in situ during isolation and purification of the compoundsor by separately reacting the purified compound in its free base or freeacid form with a suitable acid or base, respectively, and isolating thesalt thus formed.

Those of skill in the art will appreciate that compounds of the presenttechnology may exhibit the phenomena of tautomerism, conformationalisomerism, geometric isomerism and/or stereoisomerism. As the formuladrawings within the specification and claims can represent only one ofthe possible tautomeric, conformational isomeric, stereochemical orgeometric isomeric forms, it should be understood that the presenttechnology encompasses any tautomeric, conformational isomeric,stereochemical and/or geometric isomeric forms of the compounds havingone or more of the utilities described herein, as well as mixtures ofthese various different forms.

“Tautomers” refers to isomeric forms of a compound that are inequilibrium with each other. The presence and concentrations of theisomeric forms will depend on the environment the compound is found inand may be different depending upon, for example, whether the compoundis a solid or is in an organic or aqueous solution. For example, inaqueous solution, quinazolinones may exhibit the following isomericforms, which are referred to as tautomers of each other:

As another example, guanidines may exhibit the following isomeric formsin protic organic solution, also referred to as tautomers of each other:

Because of the limits of representing compounds by structural formulas,it is to be understood that all chemical formulas of the compoundsdescribed herein represent all tautomeric forms of compounds and arewithin the scope of the present technology.

Stereoisomers of compounds (also known as optical isomers) include allchiral, diastereomeric, and racemic forms of a structure, unless thespecific stereochemistry is expressly indicated. Thus, compounds used inthe present technology include enriched or resolved optical isomers atany or all asymmetric atoms as are apparent from the depictions. Bothracemic and diastereomeric mixtures, as well as the individual opticalisomers can be isolated or synthesized so as to be substantially free oftheir enantiomeric or diastereomeric partners, and these stereoisomersare all within the scope of the present technology.

The compounds of the present technology may exist as solvates,especially hydrates. Hydrates may form during manufacture of thecompounds or compositions comprising the compounds, or hydrates may formover time due to the hygroscopic nature of the compounds. Compounds ofthe present technology may exist as organic solvates as well, includingDMF, ether, and alcohol solvates among others. The identification andpreparation of any particular solvate is within the skill of theordinary artisan of synthetic organic or medicinal chemistry.

Discussion of the Present Technology

Prostate-specific membrane antigen (“PSMA”)-targeted radiotherapy ofprostate cancer (PCa) has emerged recently as a promising approach tothe treatment of disseminated disease. While PSMA is expressed byprostate cancer, PSMA is expressed on the neo-vasculature of severalother tumor types, including (but not limited to) glioma, cervicalcarcinoma, vulvar carcinoma, endometrial carcinoma, primary ovariancarcinoma, metastatic ovarian carcinoma, non-small cell lung cancer,small cell lung cancer, bladder cancer, colon cancer, primary, gastricadenocarcinoma, primary colorectal adenocarcinoma, and renal cellcarcinoma. See, e.g., Wernicke A G, Kim S, Liu H, Bander N H, Pirog E C.Prostate-specific Membrane Antigen (PSMA) Expression in theNeovasculature of Gynecologic Malignancies: Implications forPSMA-targeted Therapy. Appl Immunohistochem Mol Morphol. 2016 Feb. 9(doi: 10.1097/PAI.0000000000000297); Wang H L, Wang S S, Song W H, PanY, Yu H P, Si T G, Liu Y, Cui X N, Guo Z. Expression ofprostate-specific membrane antigen in lung cancer cells and tumorneovasculature endothelial cells and its clinical significance. PLoSOne. 2015 May 15; 10(5):e0125924 (doi: 10.1371/journal.pone.0125924);Samplaski M K, Heston W, Elson P, Magi-Galluzzi C, Hansel D E. Folatehydrolase (prostate-specific membrane antigen) 1 expression in bladdercancer subtypes and associated tumor neovasculature. Mod Pathol. 2011November; 24(11): 1521-9 (doi: 10.1038/modpathol.2011.112); Haffner M C,Kronberger I E, Ross J S, Sheehan C E, Zitt M, Muhlmann G, Ofner D,Zelger B, Ensinger C, Yang X J, Geley S, Margreiter R, Bander N H.Prostate-specific membrane antigen expression in the neovasculature ofgastric and colorectal cancers. Hum Pathol. 2009 December;40(12):1754-61 (doi: 10.1016/j.humpath.2009.06.003); Baccala A, SerciaL, Li J, Heston W, Zhou M. Expression of prostate-specific membraneantigen in tumor-associated neovasculature of renal neoplasms. Urology.2007 August; 70(2):385-90 (doi: 10.1016/j.urology.2007.03.025); andChang S S, Reuter V E, Heston W D, Bander N H, Grauer L S, Gaudin P B.Five different anti-prostate-specific membrane antigen (PSMA) antibodiesconfirm PSMA expression in tumor-associated neovasculature. Cancer Res.1999 Jul. 1; 59(13):3192-8, each of which is incorporated herein byreference.

A small number of ligands have been evaluated in patients, and whileearly tumor response is encouraging, these compounds localize to theparotid, salivary and lacrimal glands as well as the kidney, leading todose-limiting toxicities and adverse events affecting quality of life.

In the absence of stable isotopes of astatine, iodine has been utilizedas a surrogate for drug development and for predicting radiationdosimetry. Recent work has confirmed that the pharmacokinetics of thesmall molecule PSMA inhibitor ¹³¹I-DCIBzL and its astatinated analogue(2S)-2-(3-(1-carboxy-5-(4-²¹¹At-astatobenzamido)pentyl)ureido)-pentanedioicacid (“²¹¹At-6”) were similar in a preclinical prostate cancer model,such as discussed in Kiess A P, Minn I, Vaidyanathan G, et al.(2S)-2-(3-(1-Carboxy-5-(4-[211At]astatobenzamido)pentyl)ureido)-pentanedioicacid for PSMA-targeted α-particle radiopharmaceutical therapy. J NuclMed. 2016; 57:1569-1575 incorporated herein by reference.

Notable is the potential for dose-limiting toxicity in PSMA-targetedradiotherapies. It has been reported that PSMA is expressed at lowlevels in the parotid and lacrimal glands, and recent experiments haveshown that PMPA can be used to displace ⁶⁸Ga-PSMA-HBED-CC from ratsalivary glands. See O'Keefe D S, Bacich D J, Heston W D W. Comparativeanalysis of prostate-specific membrane antigen (PSMA) versus aprostate-specific membrane antigen-like gene. Prostate. 2004; 58:200-210and Wuistemann T, Nikolopoulou A, Amor-Coarasa A, et al. Protectingsalivary glands: displacement of off-target bound prostate-specificmembrane antigen ligands. Eur J Nucl Med Mol Imaging. 2016:43(Suppl1):S15, each of which is incorporated herein by reference. Thesefindings suggest that uptake of radiopharmaceuticals in these structuresis PSMA-mediated.

Indeed, dose-limiting toxicity to the salivary glands was observed for¹³¹I-MIP-1095 and high kidney uptake was also observed for ¹³¹I-MIP-1095in mice, although this did not prove to be dose-limiting during initialclinical evaluation in human of a single therapy cycle. See Zechmann CM, Afshar-Oromieh A, Armor T, et al. Radiation dosimetry and firsttherapy results with a ¹²⁴I/¹³¹I-labeled small molecule (MIP-1095)targeting PSMA for prostate cancer therapy. Eur J Nucl Med Mol Imaging.2014; 41:1280-1292, incorporated herein by reference. Moderatexerostomia has been reported for ¹⁷⁷Lu-PSMA-617, but translation of thisligand to targeted α-particle therapy as ²²⁵Ac-PSMA-617 led to severeand sustained xerostomia. See Kratochwil C, Giesel F L, Stefanova M, etal. PSMA-Targeted Radionuclide Therapy of MetastaticCastration-Resistant Prostate Cancer with ¹⁷⁷Lu-Labeled PSMA-617. J NuclMed. 2016; 57:1170-1176, Fendler W P, Reinhardt S, Ilhan H, et al.Preliminary experience with dosimetry, response and patient reportedoutcome after ¹⁷⁷Lu-PSMA-617 therapy for metastatic castration-resistantprostate cancer. Oncotarget. 2017; 8:3581-3590, and. Kratochwil C,Bruchertseifer F, Giesel F L, et al. ²²⁵Ac-PSMA-617 for PSMA targetingalpha-radiation therapy of patients with metastatic castration-resistantprostate cancer. J Nucl Med. 2016; 57:1941-1944, each of which isincorporated herein by reference.

The present technology provides compounds displaying high affinity forPSMA and appropriate affinity for human serum albumin (HSA) (alternatelydescribed herein as “double targeted constructs,” “double targetedcompounds,” and “dual targeting ligands”) in order to provide a highertherapeutic index and be suitable for treatment of cancer expressingPSMA by targeted alpha therapy (TAT). The present technology isparticularly suited to treat prostate cancer. Compositions are alsoprovided that incorporating such compounds, as are methods related tothe treatment of cancer expressing PSMA. Furthermore, the presenttechnology provides a method of enhancing uptake of a therapeutic agent,such as a double targeted construct, to a tumor presenting PSMA isprovided, by modifying the human serum albumin binding moiety of suchagents.

Thus, in an aspect, a compound according to Formula I is provided

or a pharmaceutically acceptable salt thereof, wherein X¹ is ¹²⁴I, ¹²⁵I,¹²⁷I, ¹³¹I, ²¹¹At, or Sn(R⁴)₃; R¹, R², and R³ are each independently H,methyl, benzyl, 4-methoxybenzyl, or tert-butyl; R⁴ is independently ateach occurrence an alkyl group; n is 1 or 2; and m is 0, 1, 2, or 3. Inany embodiment herein, R¹, R², and R³ may each independently be H ortert-butyl. R⁴ may independently at each occurrence be methyl, ethyl,propyl, propyl, or butyl. In any embodiment herein, it may be when n is2, then m is not 2. In any embodiment herein, it may be that X¹ is ¹²⁴I,¹²⁵I, ¹³¹I, or ²¹¹At. In any embodiment herein, the compound of FormulaI may be a compound of Formula Ia

or a pharmaceutically acceptable salt thereof.

In an aspect, a compound of Formula II is provided

or a pharmaceutically acceptable salt thereof, wherein X² is ¹²⁴I, ¹²⁵I,¹²⁷I, ¹³¹I, ²¹¹At, or Sn(R⁸)₃; R⁵, R⁶, and R⁷ are each independently H,methyl, benzyl, 4-methoxybenzyl, or tert-butyl; R⁸ is independently ateach occurrence an alkyl group; W1 is a bond or —NH-alkylene-; and p is0, 1, 2, or 3. In any embodiment herein, R⁵, R⁶, and R⁷ may eachindependently be H or tert-butyl. W¹ may be a bond or acarboxylate-substituted alkylene. In any embodiment herein, W¹ may be abond, —NH—CH(CO(O)H)—(CH₂)₃—, or —NH—CH(CO(O)H)—(CH₂)₄—. In anyembodiment herein, it may be that R⁸ is independently at each occurrencemethyl, ethyl, propyl, propyl, or butyl. In any embodiment herein, itmay be X¹ is ¹²⁴I, ¹²⁵I, ¹³¹I, or ²¹¹At. In any embodiment herein, thecompound of Formula II may be a compound of Formula IIa

or a pharmaceutically acceptable salt thereof.

In an aspect of the present technology, a composition is provided thatincludes any one of the aspects and embodiments of compounds of FormulasI-II and a pharmaceutically acceptable carrier. As used herein, a“pharmaceutically acceptable carrier” includes carriers and/orexcipients. In a related aspect, a pharmaceutical composition isprovided, the pharmaceutical composition including an effective amountof the compound of any one of the aspects and embodiments of compoundsof Formulas I-II for treating a condition; and where the condition iscancer expressing PSMA. In a further related aspect, a method isprovided that includes administering a compound of any one of theaspects and embodiments of compounds of Formulas I-II (e.g., such asadministering an effective amount) or administering a pharmaceuticalcomposition comprising an effective amount of a compound of any one ofthe aspects and embodiments of compounds of Formulas I-II to a subjectsuffering from a cancer expressing PSMA. The cancer may include one ormore of glioma, cervical carcinoma, vulvar carcinoma, endometrialcarcinoma, primary ovarian carcinoma, metastatic ovarian carcinoma,non-small cell lung cancer, small cell lung cancer, bladder cancer,colon cancer, primary, gastric adenocarcinoma, primary colorectaladenocarcinoma, renal cell carcinoma, and prostate cancer. The prostatecancer may include castration resistant prostate cancer.

“Effective amount” refers to the amount of a compound or compositionrequired to produce a desired effect. One example of an effective amountincludes amounts or dosages that yield acceptable toxicity andbioavailability levels for therapeutic (pharmaceutical) use including,but not limited to, the treatment of cancer such as prostate cancer.Another example of an effective amount includes amounts or dosages thatare capable of reducing symptoms associated with cancer, such as, forexample, reduction of the number of cancer cells in circulation. As usedherein, a “subject” or “patient” is a mammal, such as a cat, dog, rodentor primate. Typically the subject is a human, and, preferably, a humansuffering from or suspected of suffering from a cancer expressing PSMA,such as prostate cancer. The term “subject” and “patient” can be usedinterchangeably.

Thus, the instant present technology provides pharmaceuticalcompositions and medicaments comprising any of the compounds disclosedherein (e.g., compounds of Formulas I-IV) and a pharmaceuticallyacceptable carrier or one or more excipients or fillers (collectively,such carriers, excipients, fillers, etc., will be referred to as“pharmaceutically acceptable carriers” unless a more specific term isused). The compositions may be used in the methods and treatmentsdescribed herein. Such compositions and medicaments include atherapeutically effective amount of any compound as described herein,including but not limited to a compound of Formulas I-II, for treatingone or more of the herein-described conditions. The pharmaceuticalcomposition may be packaged in unit dosage form. For example, the unitdosage form is effective in treating cancer expressing PSMA whenadministered to a subject in need thereof. Such cancer expressing PSMAincludes one or more of glioma, cervical carcinoma, vulvar carcinoma,endometrial carcinoma, primary ovarian carcinoma, metastatic ovariancarcinoma, non-small cell lung cancer, small cell lung cancer, bladdercancer, colon cancer, primary, gastric adenocarcinoma, primarycolorectal adenocarcinoma, renal cell carcinoma, and prostate cancer.

The pharmaceutical compositions and medicaments may be prepared bymixing one or more compounds of the present technology, pharmaceuticallyacceptable salts thereof, stereoisomers thereof, tautomers thereof, orsolvates thereof, with pharmaceutically acceptable carriers, excipients,binders, diluents or the like to prevent and treat disorders associatedwith cancer expressing PSMA, such as prostate cancer. The compounds andcompositions described herein may be used to prepare formulations andmedicaments that prevent or treat a variety of disorders associated withsuch cancer. Such compositions can be in the form of, for example,granules, powders, tablets, capsules, syrup, suppositories, injections,emulsions, elixirs, suspensions or solutions. The instant compositionscan be formulated for various routes of administration, for example, byoral, parenteral, topical, rectal, nasal, vaginal administration, or viaimplanted reservoir. Parenteral or systemic administration includes, butis not limited to, subcutaneous, intravenous, intraperitoneal, andintramuscular, injections. The following dosage forms are given by wayof example and should not be construed as limiting the instant presenttechnology.

For oral, buccal, and sublingual administration, powders, suspensions,granules, tablets, pills, capsules, gelcaps, and caplets are acceptableas solid dosage forms. These can be prepared, for example, by mixing oneor more compounds of the instant present technology, or pharmaceuticallyacceptable salts or tautomers thereof, with at least one additive suchas a starch or other additive. Suitable additives are sucrose, lactose,cellulose sugar, mannitol, maltitol, dextran, starch, agar, alginates,chitins, chitosans, pectins, tragacanth gum, gum arabic, gelatins,collagens, casein, albumin, synthetic or semi-synthetic polymers orglycerides. Optionally, oral dosage forms can contain other ingredientsto aid in administration, such as an inactive diluent, or lubricantssuch as magnesium stearate, or preservatives such as paraben or sorbicacid, or anti-oxidants such as ascorbic acid, tocopherol or cysteine, adisintegrating agent, binders, thickeners, buffers, sweeteners,flavoring agents or perfuming agents. Tablets and pills may be furthertreated with suitable coating materials known in the art.

Liquid dosage forms for oral administration may be in the form ofpharmaceutically acceptable emulsions, syrups, elixirs, suspensions, andsolutions, which may contain an inactive diluent, such as water.Pharmaceutical formulations and medicaments may be prepared as liquidsuspensions or solutions using a sterile liquid, such as, but notlimited to, an oil, water, an alcohol, and combinations of these.Pharmaceutically suitable surfactants, suspending agents, emulsifyingagents, may be added for oral or parenteral administration.

As noted above, suspensions may include oils. Such oils include, but arenot limited to, peanut oil, sesame oil, cottonseed oil, corn oil andolive oil. Suspension preparation may also contain esters of fatty acidssuch as ethyl oleate, isopropyl myristate, fatty acid glycerides andacetylated fatty acid glycerides. Suspension formulations may includealcohols, such as, but not limited to, ethanol, isopropyl alcohol,hexadecyl alcohol, glycerol and propylene glycol. Ethers, such as butnot limited to, poly(ethyleneglycol), petroleum hydrocarbons such asmineral oil and petrolatum; and water may also be used in suspensionformulations.

Injectable dosage forms generally include aqueous suspensions or oilsuspensions which may be prepared using a suitable dispersant or wettingagent and a suspending agent. Injectable forms may be in solution phaseor in the form of a suspension, which is prepared with a solvent ordiluent. Acceptable solvents or vehicles include sterilized water,Ringer's solution, or an isotonic aqueous saline solution. An isotonicsolution will be understood as isotonic with the subject. Alternatively,sterile oils may be employed as solvents or suspending agents.Typically, the oil or fatty acid is non-volatile, including natural orsynthetic oils, fatty acids, mono-, di- or tri-glycerides.

For injection, the pharmaceutical formulation and/or medicament may be apowder suitable for reconstitution with an appropriate solution asdescribed above. Examples of these include, but are not limited to,freeze dried, rotary dried or spray dried powders, amorphous powders,granules, precipitates, or particulates. For injection, the formulationsmay optionally contain stabilizers, pH modifiers, surfactants,bioavailability modifiers and combinations of these.

Compounds of the present technology may be administered to the lungs byinhalation through the nose or mouth. Suitable pharmaceuticalformulations for inhalation include solutions, sprays, dry powders, oraerosols containing any appropriate solvents and optionally othercompounds such as, but not limited to, stabilizers, antimicrobialagents, antioxidants, pH modifiers, surfactants, bioavailabilitymodifiers and combinations of these. The carriers and stabilizers varywith the requirements of the particular compound, but typically includenonionic surfactants (Tweens, Pluronics, or polyethylene glycol),innocuous proteins like serum albumin, sorbitan esters, oleic acid,lecithin, amino acids such as glycine, buffers, salts, sugars or sugaralcohols. Aqueous and nonaqueous (e.g., in a fluorocarbon propellant)aerosols are typically used for delivery of compounds of the presenttechnology by inhalation.

Dosage forms for the topical (including buccal and sublingual) ortransdermal administration of compounds of the present technologyinclude powders, sprays, ointments, pastes, creams, lotions, gels,solutions, and patches. The active component may be mixed under sterileconditions with a pharmaceutically-acceptable carrier or excipient, andwith any preservatives, or buffers, which may be required. Powders andsprays can be prepared, for example, with excipients such as lactose,talc, silicic acid, aluminum hydroxide, calcium silicates and polyamidepowder, or mixtures of these substances. The ointments, pastes, creamsand gels may also contain excipients such as animal and vegetable fats,oils, waxes, paraffins, starch, tragacanth, cellulose derivatives,polyethylene glycols, silicones, bentonites, silicic acid, talc and zincoxide, or mixtures thereof. Absorption enhancers can also be used toincrease the flux of the compounds of the present technology across theskin. The rate of such flux can be controlled by either providing a ratecontrolling membrane (e.g., as part of a transdermal patch) ordispersing the compound in a polymer matrix or gel.

Besides those representative dosage forms described above,pharmaceutically acceptable excipients and carriers are generally knownto those skilled in the art and are thus included in the instant presenttechnology. Such excipients and carriers are described, for example, in“Remingtons Pharmaceutical Sciences” Mack Pub. Co., New Jersey (1991),which is incorporated herein by reference.

The formulations of the present technology may be designed to beshort-acting, fast-releasing, long-acting, and sustained-releasing asdescribed below. Thus, the pharmaceutical formulations may also beformulated for controlled release or for slow release.

The instant compositions may also comprise, for example, micelles orliposomes, or some other encapsulated form, or may be administered in anextended release form to provide a prolonged storage and/or deliveryeffect. Therefore, the pharmaceutical formulations and medicaments maybe compressed into pellets or cylinders and implanted intramuscularly orsubcutaneously as depot injections or as implants such as stents. Suchimplants may employ known inert materials such as silicones andbiodegradable polymers.

Specific dosages may be adjusted depending on conditions of disease, theage, body weight, general health conditions, sex, and diet of thesubject, dose intervals, administration routes, excretion rate, andcombinations of drugs. Any of the above dosage forms containingeffective amounts are well within the bounds of routine experimentationand therefore, well within the scope of the instant present technology.

Those skilled in the art are readily able to determine an effectiveamount by simply administering a compound of the present technology to apatient in increasing amounts until, for example, the size of a tumordecreases. The compounds of the present technology can be administeredto a patient at dosage levels in the range of about 0.1 to about 1,000mg per day. For a normal human adult having a body weight of about 70kg, a dosage in the range of about 0.01 to about 100 mg per kg of bodyweight per day is sufficient. The specific dosage used, however, canvary or may be adjusted as considered appropriate by those of ordinaryskill in the art. For example, the dosage can depend on a number offactors including the requirements of the patient, the severity of thecondition being treated and the pharmacological activity of the compoundbeing used. The determination of optimum dosages for a particularpatient is well known to those skilled in the art.

Various assays and model systems can be readily employed to determinethe therapeutic effectiveness of the treatment according to the presenttechnology.

Effectiveness of the compositions and methods of the present technologymay also be demonstrated by a decrease in the symptoms of cancerexpressing PSMA, such as, for example, reduction in the volume of atumor, such as prostate cancer-related tumor. Effectiveness of thecompositions and methods of the present technology may also bedemonstrated by a decrease in the population of cancer cells incirculation.

For each of the indicated conditions described herein, test subjectswill exhibit a 10%, 20%, 30%, 50% or greater reduction, up to a 75-90%,or 95% or greater, reduction, in one or more symptom(s) caused by, orassociated with, the disorder in the subject, compared toplacebo-treated or other suitable control subjects.

The compounds of the present technology can also be administered to apatient along with other conventional therapeutic agents that may beuseful in the treatment of cancer expressing PSMA, such as prostatecancer. Thus, a pharmaceutical composition of the present technology mayfurther include an anti-cancer agent different than the compounds ofFormulas I-II. The administration may include oral administration,parenteral administration, or nasal administration. In any of theseembodiments, the administration may include subcutaneous injections,intravenous injections, intraperitoneal injections, or intramuscularinjections. In any of these embodiments, the administration may includeoral administration. The methods of the present technology can alsocomprise administering, either sequentially or in combination with oneor more compounds of the present technology, a conventional therapeuticagent in an amount that can potentially or synergistically be effectivefor the treatment of cancer expressing PSMA, such as prostate cancer.

In an aspect, a compound of the present technology is administered to apatient in an amount or dosage suitable for therapeutic use. Generally,a unit dosage comprising a compound of the present technology will varydepending on patient considerations. Such considerations include, forexample, age, protocol, condition, sex, extent of disease,contraindications, concomitant therapies and the like. An exemplary unitdosage based on these considerations can also be adjusted or modified bya physician skilled in the art. For example, a unit dosage for a patientcomprising a compound of the present technology can vary from 1×10⁻⁴g/kg to 1 g/kg, preferably, 1×10⁻³ g/kg to 1.0 g/kg. Dosage of acompound of the present technology can also vary from 0.01 mg/kg to 100mg/kg or, preferably, from 0.1 mg/kg to 10 mg/kg.

A compound of the present technology can also be modified, for example,by the covalent attachment of an organic moiety or conjugate to improvepharmacokinetic properties, toxicity or bioavailability (e.g., increasedin vivo half-life). The conjugate can be a linear or branchedhydrophilic polymeric group, fatty acid group or fatty acid ester group.A polymeric group can comprise a molecular weight that can be adjustedby one of ordinary skill in the art to improve, for example,pharmacokinetic properties, toxicity or bioavailability. Exemplaryconjugates can include a polyalkane glycol (e.g., polyethylene glycol(PEG), polypropylene glycol (PPG)), carbohydrate polymer, amino acidpolymer or polyvinyl pyrolidone and a fatty acid or fatty acid estergroup, each of which can independently comprise from about eight toabout seventy carbon atoms. Conjugates may include polyethylene amine(PEI), polyglycine, hybrids of PEI and polyglycine, polyethylene glycol(PEG) or methoxypolyethylene glycol (mPEG). Conjugates for use with acompound of the present technology can, in one aspect, improve in vivohalf-life. Other exemplary conjugates for use with a compound of thepresent technology as well as applications thereof and relatedtechniques include those generally described by U.S. Pat. No. 5,672,662,which is hereby incorporated by reference herein.

The present technology provides methods of identifying a target ofinterest including contacting the target of interest with a detectableor imaging effective quantity of a compound of the present technology. Adetectable or imaging effective quantity is a quantity of a compound ofthe present technology necessary to be detected by the detection methodchosen. For example, a detectable quantity can be an administered amountsufficient to enable detection of binding of the labeled compound to atarget of interest including, but not limited to, cancer expressing PSMAsuch as glioma, cervical carcinoma, vulvar carcinoma, endometrialcarcinoma, primary ovarian carcinoma, metastatic ovarian carcinoma,non-small cell lung cancer, small cell lung cancer, bladder cancer,colon cancer, primary, gastric adenocarcinoma, primary colorectaladenocarcinoma, renal cell carcinoma, and/or prostate cancer. Uponbinding of the labeled compound to the target of interest, the targetmay be isolated, purified and further characterized such as bydetermining the amino acid sequence of a protein to which the compoundof the present technology is bound.

The terms “associated” and/or “binding” can mean a chemical or physicalinteraction, for example, between a compound of the present technologyand a target of interest. Examples of associations or interactionsinclude covalent bonds, ionic bonds, hydrophilic-hydrophilicinteractions, hydrophobic-hydrophobic interactions and complexes.Associated can also refer generally to “binding” or “affinity” as eachcan be used to describe various chemical or physical interactions.Measuring binding or affinity is also routine to those skilled in theart. For example, compounds of the present technology can bind to orinteract with a target of interest or precursors, portions, fragmentsand peptides thereof and/or their deposits.

In an aspect, a method of enhancing uptake of a therapeutic agent to atumor presenting prostate specific membrane antigen (“PSMA”) isprovided, where the method includes administering a first therapeuticagent includes a PMSA-targeting moiety and a human serum albumin bindingmoiety to a subject with one or more cancer tumors expressing PSMA,where the human serum albumin binding moiety includes a radionuclide;detecting distribution of the first therapeutic agent in the subject;and modifying the first therapeutic agent to provide a secondtherapeutic agent. The second therapeutic agent is, of course, of adifferent structure than the first therapeutic agent. The secondtherapeutic agent may therefore be described as including the samePMSA-targeting moiety of the first therapeutic agent and a second humanserum albumin binding moiety. The PMSA-targeting moiety may include aglutamate-urea-glutamate moiety or a glutamate-urea-lysine moiety. Thecancer expressing PSMA may be one or more of glioma, cervical carcinoma,vulvar carcinoma, endometrial carcinoma, primary ovarian carcinoma,metastatic ovarian carcinoma, non-small cell lung cancer, small celllung cancer, bladder cancer, colon cancer, primary, gastricadenocarcinoma, primary colorectal adenocarcinoma, renal cell carcinoma,and prostate cancer. The prostate cancer may be castration resistantprostate cancer.

The human serum albumin binding moiety may include a ¹²⁴I-substituted, a¹²⁵I-substituted, a ¹³¹I-substituted, or a ²¹¹At-substituted phenylmoiety. The human serum albumin binding moiety may include a4-(¹²⁴I)-substituted, a 4-(¹²⁵I)-substituted, a 4-(¹³¹I)-substituted, or4-(²¹¹At)-substituted phenyl moiety. The human serum albumin bindingmoiety may include a 1,4-phenylene where the group at the 4 position is¹²⁴I, ¹²⁵I ¹³¹I, or ²¹¹At. In any embodiment herein, modifying the firsttherapeutic agent may include lengthening or shortening a hydrocarbonchain of the human serum albumin binding moiety. Modifying the firsttherapeutic agent may include conjugating a polyalkane glycol (e.g.,polyethylene glycol (PEG), polypropylene glycol (PPG),methoxypolyethylene glycol (mPEG)), polyethylene amine (PEI),polyglycine, hybrids of PEI and polyglycine, carbohydrate polymer, aminoacid polymer, polyvinyl pyrolidone, a fatty acid, and/or a fatty acidester group to the human serum albumin binding moiety. The conjugatingstep may include inserting a polyalkane glycol, polyethylene amine(PEI), polyglycine, carbohydrate polymer, amino acid polymer, polyvinylpyrolidone, a fatty acid, a fatty acid ester group, or a combination ofany two or more thereof between the PSMA-targeting moiety and the humanserum albumin binding moiety. The conjugating step may includeconjugating a polyalkane glycol, polyethylene amine (PEI), polyglycine,carbohydrate polymer, amino acid polymer, polyvinyl pyrolidone, a fattyacid, a fatty acid ester group, or a combination of any two or morethereof at a position on the human serum albumin binding moiety that isdistal to the PSMA-targeting moiety. In any embodiment herein, the firsttherapeutic agent may be a compound of Formula I or II; in anyembodiment herein, the second therapeutic agent may be a compound ofFormula I or II.

The method may include administering the second therapeutic agent to asubject with one or more cancer tumors expressing PSMA and detectingdistribution of the second therapeutic agent in the subject. Due to themodification of the first therapeutic agent, the second therapeuticagent may exhibit a higher tumor uptake in comparison with non-tumortissues of the subject than was exhibited by the first therapeuticagent. In any embodiment of the method, it may be that administering thefirst therapeutic agent includes parenteral administration, such asintravenous administration and/or intra-arterial administration.

The examples herein are provided to illustrate advantages of the presenttechnology and to further assist a person of ordinary skill in the artwith preparing or using the compounds of the present technology orsalts, pharmaceutical compositions, derivatives, solvates, metabolites,prodrugs, racemic mixtures or tautomeric forms thereof. The examplesherein are also presented in order to more fully illustrate thepreferred aspects of the present technology. The examples should in noway be construed as limiting the scope of the present technology, asdefined by the appended claims. The examples can include or incorporateany of the variations, aspects or aspects of the present technologydescribed above. The variations, aspects or aspects described above mayalso further each include or incorporate the variations of any or allother variations, aspects or aspects of the present technology.

EXAMPLES

General Synthetic and Analytical Details:

All solvents were purchased from Sigma Aldrich and were of reagent gradequality unless otherwise indicated. Solvents were dried either bydistillation over an activated stainless steel column (Pure ProcessTechnology, LLC) column or by drying over activated molecular sieves.Reagents were purchased from Sigma Aldrich or Alfa Aesar and were ofreagent grade. All reactions described below were carried out in driedglassware. Purifications were performed using silica chromatography onVWR® High Purity Silica Gel 60 Å or flash chromatography using aCombiFlash Rf+ (Teledyne Isco). Preparative HPLC was performed using anXBridge™ Prep C18 5 μm OBD™ 19×100 mm column (Waters) on a dual pumpAgilent ProStar HPLC fitted with an Agilent ProStar 325 Dual WavelengthUV-Vis Detector. UV absorption was monitored at 220 nm and 280 nm. Abinary solvent system was used, with solvent A comprising H₂O+0.01% TFAand solvent B consisting of 90% v/v MeCN/H₂O+0.01% TFA. Purification wasachieved at a flow rate of 12 mL/min and with the following gradientHPLC method: 0% B 0-1 min., 0-100% B 1-28 mins, 100-0% B 28-30 mins.Final products were identified and characterized using thin layerchromatography, analytical HPLC, mass spectroscopy and NMR spectroscopy.Analytical HPLC was performed using an XSelect™ CSH™ C18 5 μm 4.6×50 mmcolumn (Waters) at a flow rate of 2 mL/min and a gradient of 0-100% Bover 10 min. Mass determinations were performed by LCMS analysis using aWaters ACQUITY UPLC® coupled to a Waters SQ Detector 2. NMR analyseswere performed using a Bruker Avance III 500 MHz spectrometer. Spectraare reported as ppm and are referenced to the solvent resonances inDMSO-d6 or chloroform-d (Sigma Aldrich). The purity of all compoundsevaluated in the biological assay was >95% purity as judged by LC-MS and¹H NMR.

Representative Synthesis of Compounds of the Present Technology.

Representative synthetic procedures are provided below in Scheme 1. Inthese exemplary compounds, the use of iodine and/or radioiodine is to befurther understood as a surrogate for the radiohalogen ²¹¹At. See Kelly,J. M., Amor-Coarasa, A., Nikolopoulou A., Wiustemann T., Barelli, P.,Kim, D., Williams, C. Jr, Zheng X., Bi C., Hu, B., Warren J. D., Hage D.S., DiMagno S. G., and Babich J. W. Double Targeting Ligands withModulated Pharmacokinetics for Endoradiotherapy of Prostate Cancer, J.Nucl. Med. (Apr. 27, 2017) (doi: 10.2967/jnumed.116.188722),incorporated herein by reference.

The synthesis of exemplary compounds are provided below.

Di-tert-butyl(((S)-6-amino-1-(tert-butoxy)-1-oxohexan-2-yl)carbamoyl)-L-glutamate(EuK.3OtBu) (1)

The title compound was synthesized according to protocols described inMaresca K P, Hillier S M, Femia F J, Barone DKC, Joyal J L, Zimmerman CN, Kozikowski A P, Barrett J A, Eckelman W C, Babich J W. A series ofhalogenated heterodimeric inhibitors of prostate specific membraneantigen (PSMA) as radiolabeled probes for targeting prostate cancer. J.Med. Chem. 2009; 52:347-357, incorporated herein by reference.H-Glu(OtBu)-OtBu.HCl (2.96 g, 10 mmol) was suspended in CH₂Cl₂ (20 mL)at 0° C. and stirred under Ar. To the stirred suspension was added DMAP(50 mg, 0.4 mmol) and NEt₃ (3.6 mL, 25.7 mmol). The resulting mixturewas stirred for 5 min at 0° C. Then a fine suspension of2-carbonyldiimidazole (1.78 g, 11 mmol) in CH₂Cl₂ (15 mL) was added, andthe reaction was stirred overnight under Ar with warming to rt. It wasthen diluted with CH₂Cl₂ (30 mL) and washed with saturated NaHCO₃solution, H₂O (×2) and saturated NaCl solution. The organic fraction wasdried over MgSO₄, filtered and concentrated under reduced pressure togive a clear oil. This crude product was purified by flashchromatography (EtOAc/hexane; 0-10% EtOAc over 12 min, then 10-30% EtOAcfrom 12-16 min, then 30% EtOAc from 16-20 min), and di-tert-butyl(1H-imidazole-1-carbonyl)-L-glutamate (Eu.2OtBu) was isolated as a clearoil (2.14 g; 61%).

To a solution of compound Eu.2OtBu (293 mg, 0.83 mmol) in1,2-dichloroethane (6 mL) cooled to 0° C. was added MeOTf (93 μL, 0.85mmol) and NEt₃ (237 μL, 1.70 mmol), and the resulting mixture wasstirred for 30 min under Ar. Then H-Lys(Z)-OtBu.HCl (310 mg, 0.83 mmol)was added in one portion and the reaction was stirred for 4 h at 40° C.It was then cooled to rt and concentrated under reduced pressure. Thecrude product was dissolved in CH₂Cl₂ (15 mL), washed with 1% v/v AcOHsolution, dried over MgSO₄, filtered and concentrated under reducedpressure to give an oil. The oil was purified by silica chromatography(EtOAc:hexane=1:1) to give tri-tert-butyl(9S,13S)-3,11-dioxo-1-phenyl-2-oxa-4,10,12-triazapentadecane-9,13,15-tricarboxylate(EuK(Z).3OtBu) as a colorless oil that partially solidified uponstanding (284 mg; 55%).

To a solution of EuK(Z).3OtBu (284 mg, 0.46 mmol) in EtOH (6 mL) wasadded 10% palladium on carbon (8 mg). The suspension was heated to 40°C. and stirred overnight under an H₂ atmosphere. Then the reaction wascooled to rt and filtered through celite. The celite was washed withMeOH and the organic layers were combined and concentrated under reducedpressure to give EuK.3OtBu (1) as a colorless oil (95 mg; 44%).

Di-tert-butyl(((S)-5-amino-1-(tert-butoxy)-1-oxopentan-2-yl)carbamoyl)-L-glutamate(EuO.3OtBu) (2)

A solution of MeOTf (248 μL, 2.27 mmol) and NEt₃ (700 μL, 5.00 mmol) in1,2-dichloroethane (3 mL) was added to a solution of 794 mg (2.25 mmol)Eu.2OtBu in 1,2-dichloroethane (7 mL) at 0° C. under Ar. The mixture wasstirred at 0° C. for 30 min before MeOTf (124 μL, 1.14 mmol) was added.The resulting mixture was stirred for an additional 30 min at 0° C.,then H-Orn(Z)-OtBu.HCl (807 mg, 2.25 mmol) was added in one portion andthe reaction was heated to 40° C. for 3 h. It was then cooled to rt andwashed with H₂O. The organic layer was dried over MgSO₄, filtered andconcentrated under reduced pressure to give a colorless oil. The oil waspurified by flash chromatography (50% EtOAC in hexane to 100% EtOAc over15 min) to give the product tri-tert-butyl(8S,12S)-3,10-dioxo-1-phenyl-2-oxa-4,9,11-triazatetradecane-8,12,14-tricarboxylate(EuO(Z).3OtBu) as a clear oil (950 mg; 69%). ¹H NMR (500 MHz, CDCl₃) δ7.35-7.30 (m, 5H), 5.13 (m, 3H), 5.09 (s, 2H), 4.34 (m, 2H), 3.21 (m,2H), 2.30 (m, 2H), 2.09 (m, 1H), 1.86 (m, 2H), 1.66-1.56 (m, 3H), 1.45(s, 18H), 1.44 (s, 9H). ESI(+)=608.5 [M+H]⁺. Calculated mass: 607.8

EuO(Z).3OtBu (950 mg, 1.56 mmol) was dissolved in EtOH (10 mL) andtransferred to a round bottom flask containing 10% palladium on carbon(12 mg). The suspension was stirred overnight at rt under H₂ atmosphere,and was then filtered through celite. The celite was washed with MeCN,and the combined organic fractions were concentrated under reducedpressure. The product EuO.3OtBu (2) was isolated as a white foam (600mg; 81%). ¹H NMR (500 MHz, CDCl₃) δ 8.20 (br s, 2H), 6.43 (d, 1H, J=7.7Hz), 6.28 (d, 1H, J=8.1 Hz), 4.35 (m, 2H), 3.10 (m, 2H), 2.34 (m, 2H),2.07 (m, 2H), 1.85 (m, 4H), 1.45 (s, 18H), 1.43 (s, 9H). ESI(+)=474.6[M+H]⁺. Calculated mass: 473.3

(S)-5-(tert-Butoxy)-4-(3-((S)-1,5-di-tert-butoxy-1,5-dioxopentan-2-yl)ureido)-5-oxopentanoicacid (EuE.3OtBu) (3)

To a solution of Eu.2OtBu (200 mg, 0.57 mmol) in 1,2-dichloroethane (8mL) cooled to 0° C. were added solutions of MeOTf (66 μL, 0.60 mmol) in1,2-dichloroethane (1 mL) and NEt₃ (158 μL, 1.13 mmol) in1,2-dichloroethane (1 mL). The resulting mixture was stirred for 30 minunder Ar, warming to rt. Then H-Glu(OBzl)-OtBu.HCl (188 mg, 0.57 mmol)was added in one portion and the reaction mixture was stirred at rt for3 h. The reaction was washed with H₂O and the organic layer was driedover MgSO₄, filtered and concentrated under reduced pressure to give aclear oil, EuE(OBz).3OtBu (240 mg; 73%), that was used without furtherpurification. ¹H NMR (500 MHz, CDCl₃) δ 7.38-7.32 (m, 5H), 5.12 (d, 2H,J=3.0 Hz), 5.03 (m, 2H), 4.37 (m, 1H), 4.32 (m, 1H), 2.53-2.21 (m, 4H),2.11 (m, 1H), 2.04 (m, 1H), 1.92 (m, 1H), 1.85 (m, 1H), 1.46 (s, 9H),1.45 (s, 9H), 1.44 (s, 9H). ESI(+)=579.6 [M+H]⁺. Calculated mass: 578.3To a solution of EuE(OBz).3OtBu (210 mg, 0.36 mmol) in EtOH (5 mL) wasadded 10% palladium on carbon (14 mg) while N₂ was bubbled through thesolution. The suspension was stirred for 4 h under H₂ atmosphere andthen filtered through celite and concentrated under reduced pressure togive EuE.3OtBu (3) as a colorless oil (178 mg; 99%). ¹H NMR (500 MHz,CDCl₃) δ 4.37 (m, 1H), 4.29 (m, 1H), 2.40 (m, 2H), 2.29 (m, 2H), 2.14(m, 1H), 2.07 (m, 1H), 1.85 (m, 2H), 1.46 (s, 9H), 1.44 (s, 9H), 1.42(s, 9H). ESI(+)=489.4 [M+H]⁺. Calculated mass: 488.3

(((S)-1-Carboxy-5-(4-(4-iodophenyl)butanamido)pentyl)carbamoyl)-L-glutamicacid (RPS-005)

To a solution of 90 mg (185 μmol) EuK.3OtBu (1) in CH₂Cl₂ (5 mL) wasadded a solution of 4-(4-iodophenyl) butanoic acid (54 mg, 185 μmol) andEDC (34 mg, 221 μmol) in CH₂Cl₂ (5 mL). The mixture was stirred for 10min, then DIPEA (38 μL, 221 μmol) was added and the reaction was stirredat rt for 4 h. The mixture was diluted with CH₂Cl₂ (10 mL) and washedwith 1N HCl (10 mL), saturated NaHCO₃ (10 mL), and brine (20 mL). Theorganic layer was dried over Na₂SO₄ and concentrated to afford the crudeproduct. The crude product was purified by flash chromatography (0-100%EtOAc in hexane), and EuK-IPBA.3OtBu (4) was isolated as a white solid(96 mg, 68%). ¹H NMR (500 MHz, CDCl₃) δ 7.54 (d, 2H, J=8.1 Hz), 6.91 (d,2H, J=8.1 Hz), 6.67 (m, 1H), 5.81 (d, 1H, J=8.1 Hz), 5.58 (d, 1H, J=7.7Hz), 4.30 (m, 1H), 4.18 (m, 1H), 3.23 (m, 1H), 3.13 (m, 1H), 2.56 (t,2H, J=7.6 Hz), 2.29 (m, 2H), 2.18 (t, 2H, J=7.4 Hz), 2.05 (m, 1H), 1.90(m, 2H), 1.80 (m, 1H), 1.70 (m, 1H), 1.51-1.44 (m, 3H), 1.41 (s, 9H),1.38 (s, 18H), 1.28 (m, 2H). ESI(+)=760.2 [M+H]⁺. Calculated mass: 759.3

EuK-IPBA.3OtBu (4) (75 mg, 99 μmol) was dissolved in 2 mL CH₂Cl₂ and 2mL TFA and stirred for 3 h at rt. The solvent was removed under a streamof N₂ and the crude product was purified by prep HPLC (15% B to 100% B).The peak corresponding to the product was collected and lyophilized andRPS-005 was isolated as a white solid residue (33 mg; 57%). ¹H NMR (500MHz, DMSO) δ 7.76 (m, 1H), 7.62 (d, 2H, J=7.7 Hz), 7.01 (d, 2H, J=7.6Hz), 6.30 (m, 2H), 4.09 (m, 1H), 4.04 (m, 1H), 3.00 (m, 2H), 2.50 (2H),2.26 (m, 2H), 2.04 (t, 2H, J=7.3 Hz), 1.91 (m, 1H), 1.75 (m, 3H), 1.64(m, 1H), 1.53 (m, 1H), 1.38 (m, 2H), 1.27 (m, 2H). ESI(+) 592.2=[M+H]⁺.Calculated mass: 591.1

(((S)-1-Carboxy-4-(4-(4-iodophenyl)butanamido)pentyl)carbamoyl)-L-glutamicacid (RPS-020)

To a stirred suspension of 4-(p-iodophenyl)butyric acid (93 mg, 0.32mmol) and HBTU (151 mg, 0.40 mmol) in CH₂Cl₂ (3 mL) was added a solutionof NEt₃ (56 μL, 0.40 mmol) in CH₂Cl₂ (4 mL), and the resulting mixturewas stirred at rt under Ar for 5 min. Then a solution of EuO.3OtBu (2)(150 mg, 0.32 mmol) in CH₂Cl₂ (3 mL) was added, and the reaction wasstirred overnight at rt. The solvent was evaporated under reducedpressure, and the crude product was purified by flash chromatography(100% hexane to 100% EtOAc over 12 min). The product EuO-IPBA.3OtBu (5)was isolated as a pale oil (125 mg; 52%). ¹H NMR (500 MHz, CDCl₃) δ 7.59(d, 2H, J=8.3 Hz), 6.95 (d, 2H, J=8.3 Hz), 6.28 (br s, 1H), 5.35 (d, 1H,J=8.2 Hz), 5.30 (d, 1H, J=7.9 Hz), 4.32 (m, 2H), 3.26 (m, 2H), 2.60 (t,2H, J=7.7 Hz), 2.33 (m, 2H), 2.19 (t, 2H, J=7.5 Hz), 2.07 (m, 1H), 1.95(quint, 2H, J=7.3 Hz), 1.83 (m, 1H), 1.75 (m, 1H), 1.60 (m, 1H), 1.56(m, 2H), 1.47 (s, 9H), 1.45 (s, 9H), 1.44 (s, 9H). ESI(+)=746.5 [M+H]⁺.Calculated mass: 745.3

EuO-IPBA.3OtBu (5) (30 mg, 40 μmol) was dissolved in 1 mL CH₂Cl₂ and 1mL TFA and stirred overnight at rt. The solvent was removed under astream of N₂ and the crude product was purified by prep HPLC (15% B to100% B). The peak corresponding to the product was collected andlyophilized and RPS-020 was isolated as a white solid residue (19 mg;82%). ¹H NMR (500 MHz, DMSO) δ 7.83 (t, 1H, J=5.6 Hz), 7.65 (d, 2H,J=8.3 Hz), 7.03 (d, 2H, J=8.3 Hz), 6.36 (d, 1H, J=8.2 Hz), 6.31 (d, 1H,J=8.2 Hz), 4.12 (m, 1H), 4.07 (m, 1H), 3.04 (m, 2H), 2.51 (t, 2H, J=7.7Hz), 2.25 (m, 2H), 2.06 (t, 2H, J=7.5 Hz), 1.95 (m, 1H), 1.81-1.66 (m,4H), 1.53 (m, 1H), 1.41 (m, 1H). ESI(+)=578.2 [M+H]+; ESI(−)=576.3[M−H]⁻ Calculated mass: 577.1

(((S)-1-Carboxy-4-(3-(4-iodophenyl)propanamido)pentyl)carbamoyl)-L-glutamicacid (RPS-022)

To a solution of 3-(p-iodophenyl)propanoic acid (63 mg, 0.22 mmol) andEDC.HCl (57 mg, 0.30 mmol) in CH₂Cl₂ (5 mL) was added NEt₃ (84 μL, 0.60mmol) and the reaction was stirred at rt under Ar for 30 min. Then asolution of EuO.3OtBu (2) (103 mg, 0.22 mmol) in CH₂Cl₂ (1 mL) was addedand the reaction was stirred overnight at rt under Ar. The reaction wasdiluted with 10 mL CH₂Cl₂ and washed successively with H₂O and saturatedNaCl solution. The organic layer was dried over MgSO₄, filtered andconcentrated under reduced pressure to give the crude product as a paleoil. The crude product was purified by flash chromatography (100% hexaneto 100% EtOAc over 20 min), and EuO-IPPA.3OtBu (6) was isolated as aclear oil (87 mg; 53%). ¹H NMR (500 MHz, CDCl₃) δ 7.57 (d, 2H, J=8.2Hz), 6.96 (d, 2H, J=8.2 Hz), 6.61 (br s, 1H), 5.61 (d, 1H, J=8.2 Hz),5.44 (d, 1H, J=7.8 Hz), 4.34 (m, 1H), 4.23 (m, 1H), 3.29-3.16 (m, 2H),2.90 (t, 2H, J=7.8 Hz), 2.46 (t, 2H, J=7.8 Hz), 2.27 (m, 2H), 2.09 (m,1H), 1.85 (m, 1H), 1.73 (m, 1H), 1.58-1.40 (m, 3H), 1.46 (s, 9H), 1.42(s, 18H). ESI(+)=732.4 [M+H]⁺. Calculated mass: 731.3

EuO-IPPA.3OtBu (6) (7.7 mg, 10.5 μmol) was dissolved CH₂Cl₂ (1 mL) andTFA (1 mL) and stirred overnight at rt. The solvent was removed under astream of N₂ and the crude residue was lyophilized to give RPS-022 as awhite solid residue (2.5 mg; 42%). ¹H NMR (500 MHz, DMSO) δ 7.84 (t, 1H,J=5.6 Hz), 7.60 (d, 2H, J=8.3 Hz), 7.01 (d, 2H, J=8.3 Hz), 6.34 (d, 1H,J=8.3 Hz), 6.29 (d, 1H, J=8.3 Hz), 4.09 (m, 1H), 4.04 (m, 1H), 3.00 (m,2H), 2.75 (t, 2H, J=7.8 Hz), 2.32 (t, 2H, J=7.8 Hz), 2.23 (m, 2H), 1.91(m, 1H), 1.71 (m, 1H), 1.62 (m, 1H), 1.49 (m, 1H), 1.38 (m, 2H).ESI(+)=564.1 [M+H]+; 562.2 [M−H]⁻. Calculated mass: 563.1

(((S)-1-Carboxy-4-(2-(4-iodophenyl)acetamido)pentyl)carbamoyl)-L-glutamicacid (RPS-023)

To a stirred suspension of 2-(p-iodophenyl)acetic acid (26 mg, 0.10mmol) and HBTU (50 mg, 0.13 mmol) in CH₂Cl₂ (3 mL) was added a solutionof EuO.3OtBu (2) (50 mg, 0.11 mmol) and NEt₃ (19 μL, 0.13 mmol) inCH₂Cl₂ (0.5 mL), and the resulting mixture was stirred overnight at rtunder Ar. The solvent was removed under reduced pressure and the cruderesidue was purified by silica chromatography (33% EtOAc in hexane to100% EtOAc). EuO-IPAA.3OtBu (7) was isolated as a clear oil (48 mg;67%). ¹H NMR (500 MHz, MeOD) δ 7.58 (d, 2H, J=8.4 Hz), 7.02 (d, 2H,J=8.4 Hz), 4.14 (m, 1H), 4.09 (m, 1H), 3.39 (s, 2H), 3.14 (t, 2H, J=6.7Hz), 2.26 (m, 2H), 1.99 (m, 1H), 1.77 (m, 1H), 1.69 (m, 1H), 1.50 (m,3H), 1.42 (s, 9H), 1.41 (s, 18H). ESI(+)=718.4 [M+H]⁺. Calculated mass:717.3

EuO-IPAA.3OtBu (7) (10 mg, 14 μmol) was dissolved in CH₂Cl₂ (1 mL) andTFA (1 mL) and stirred at rt for 4 h. The solvent was removed under astream of N₂ and the crude product was lyophilized to give RPS-023 as awhite solid residue (6.2 mg; 81%). ¹H NMR (500 MHz, DMSO) δ 8.08 (t, 1H,J=5.4 Hz), 7.64 (d, 2H, J=8.2 Hz), 7.05 (d, 2H, J=8.2 Hz), 6.32 (m, 2H),4.08 (m, 2H), 3.34 (s, 2H), 3.03 (m, 2H), 2.23 (m, 2H), 1.91 (m, 1H),1.72-1.62 (m, 2H), 1.51 (m, 1H), 1.41 (m, 2H). ESI(+)=550.2 [M+H]+;548.2 [M−H]⁻ Calculated mass: 549.1

(3S,7S,12S)-21-(4-iodophenyl)-5,10,18-trioxo-4,6,11,17-tetraazahenicosane-1,3,7,12-tetracarboxylicacid (RPS-025)

A solution of EuE.3OtBu (3) (140 mg, 0.29 mmol) and EDC.HCl (60 mg, 0.32mmol) in 1,2-dichloroethane (5 mL) was stirred at rt under Ar for 30min. Then a fine suspension of H₂N-Lys(CBz)-OtBu.HCl (108 mg, 0.29 mmol)and NEt₃ (126 uL, 0.70 mmol) in 1,2-dichloroethane (5 mL) was added andthe mixture was stirred overnight at rt under Ar. The reaction wasdiluted with CH₂Cl₂ (5 mL) and poured into H₂O (10 mL). The layers wereseparated and the organic layer was washed with saturated NaCl solution,dried over MgSO₄, filtered and concentrated under reduced pressure togive a pale oil. The crude product was purified by flash chromatography(0% to 100% EtOAc in hexanes over 11 min, then 100% EtOAc for 7 min) andtetra-tert-butyl(9S,14S,18S)-3,11,16-trioxo-1-phenyl-2-oxa-4,10,15,17-tetraazaicosane-9,14,18,20-tetracarboxylate(EuEK(Z).4OtBu) was isolated as a clear oil (94 mg; 41%). ¹H NMR (500MHz, CDCl₃) δ 7.36-7.23 (m, 6H), 5.93 (d, 1H, J=8.4 Hz), 5.30 (d, 1H,J=8.8 Hz), 5.08 (d, 1H, J=8.7 Hz), 5.06 (s, 2H), 4.43 (m, 1H), 4.35 (m,1H), 4.24 (m, 1H), 3.16 (m, 2H), 2.29-2.22 (m, 3H), 2.17-2.07 (m, 2H),2.04 (m, 1H), 1.90 (m, 1H), 1.73 (m, 2H), 1.63 (m, 1H), 1.46-1.39 (m,4H), 1.45 (s, 9H), 1.44 (s, 9H), 1.42 (s, 9H), 1.41 (s, 9H).ESI(+)=807.8 [M+H]⁺. Calculated mass: 806.5

EuEK(Z).4OtBu (37 mg, 46 μmol) was dissolved in EtOH (4 mL). Then 10%palladium on carbon (8 mg) was added and the suspension was stirredovernight under H₂ atmosphere. The mixture was filtered through celiteand the filtrate was concentrated under reduced pressure to giveEuEK.4OtBu as a clear oil that solidified upon standing (24 mg; 78%). ¹HNMR (500 MHz, CDCl₃) δ 8.19 (br s, 2H), 7.65 (br s, 1H), 6.27 (m, 2H),4.32 (m, 2H), 4.10 (m, 1H), 3.06 (m, 2H), 2.39 (m, 2H), 2.33 (m, 2H),2.02 (m, 1H), 1.96 (m, 1H), 1.78 (m, 4H), 1.56-1.39 (m, 4H), 1.44 (s,18H), 1.42 (s, 18H). ESI(+)=673.7 [M+H]⁺. Calculated mass: 672.4

4-(p-Iodophenyl)butyric acid (580 mg, 2.0 mmol) and N-hydroxysuccinimide(345 mg, 3.0 mmol) were dissolved in CH₂Cl₂ (10 mL) and cooled to 0° C.under Ar. A solution of DCC (620 mg, 3.0 mmol) in CH₂Cl₂ (4 mL) wasadded dropwise over 10 min, and the reaction was warmed to rt andstirred overnight at rt. The reaction was filtered to remove theinsoluble urea by-product, and the filter cake was washed with CH₂Cl₂.The organic fractions were combined and concentrated under reducedpressure, and the crude product was purified by silica chromatography(EtOAC:hexane=1:1) to give N-succinimidyl 4-(p-iodophenyl)butanoate as awhite solid (400 mg, 52%). ¹H NMR (500 MHz, CDCl₃) δ 7.61 (d, 2H, J=8.2Hz), 6.96 (d, 2H, J=8.2 Hz), 2.85 (br s, 4H), 2.68 (t, 2H, J=7.6 Hz),2.60 (t, 2H, J=7.3 Hz), 2.04 (quint, 2H, J=7.4 Hz).

A solution of DIPEA (45 μL, 0.25 mmol) in 1,2-dichloroethane (1 mL) wasadded to a solution of EuEK.4OtBu (80 mg, 0.12 mmol) and N-succinimidyl4-(p-iodophenyl)butanoate (46 mg, 0.12 mmol) and stirred overnight at rtunder Ar. The mixture was concentrated under reduced pressure and thecrude residue was purified by silica chromatography (20%-100% EtOAc inhexane). The product EuEK-IPBA.4OtBu (8) was isolated as a clear oilthat solidified upon standing (58 mg; 52%). ¹H NMR (500 MHz, CDCl₃) δ7.57 (d, 2H, J=8.2 Hz), 7.22 (d, 1H, J=7.6 Hz), 6.92 (d, 2H, J=8.2 Hz),5.91 (m, 2H), 5.32 (d, 1H, J=8.8 Hz), 4.42 (m, 1H), 4.30 (m, 1H), 4.25(m, 1H), 3.20 (m, 2H), 2.57 (t, 2H, J=7.6 Hz), 2.32 (t, 2H, J=7.6 Hz),2.26 (m, 1H), 2.20-2.10 (m, 5H), 2.03 (m, 1H), 1.94-1.90 (m, 3H), 1.77(m, 2H), 1.64 (m, 1H), 1.50-1.38 (m, 4H), 1.45 (s, 18H), 1.43 (s, 9H),1.42 (s, 9H). ESI(+)=945.1 [M+H]⁺. Calculated mass: 944.4

EuEK-IPBA.4OtBu (8) (1.9 mg, 2.0 μmol) was dissolved in CH₂Cl₂ (0.5 mL)and TFA (0.5 mL) and stirred overnight at rt. The solvent was removedunder a stream of N₂ and the crude product was diluted in H₂O andpurified by prep HPLC. The fraction containing the desired product wascollected and lyophilized to give RPS-025 as a white powder (1.4 mg;97%). ¹H NMR (500 MHz, DMSO) δ 7.81 (br s, 1H), 7.64 (d, 2H, J=8.2 Hz),7.02 (d, 2H, J=8.2 Hz), 6.56 (s, 1H), 6.37 (m, 2H), 4.12 (m, 3H), 3.02(m, 2H), 2.51 (t, 2H, J=7.6 Hz), 2.28-2.17 (m, 4H), 2.05 (t, 2H, J=7.5Hz), 1.93 (m, 2H), 1.78-1.63 (m, 5H), 1.57 (m, 1H), 1.37 (m, 2H), 1.29(m, 2H). ESI(+)=721.1 [M+H]⁺. Calculated mass: 720.2

(((S)-1-Carboxy-5-(3-(4-iodophenyl)propanamido)pentyl)carbamoyl)-L-glutamicacid (RPS-026)

To a solution of 3-(p-iodophenyl)propanoic acid (85 mg, 0.308 mmol),HOAt (0.6M in THF, 0.51 mL, 0.308 mmol) and HATU (175 mg, 0.461 mmol) inDMF (1 mL) cooled to 0° C. under Ar was added a solution of EuK.3OtBu(1) (150 mg, 0.308 mmol) in DMF (1 mL). The mixture was stirred for 10min, then (0.107 mL, 0.615 mmol) DIPEA. The reaction was stirred for 20min at 0° C., and then for a further 3 h while warming to rt. Themixture was diluted with EtOAC (25 mL) and washed with 1N HCl, saturatedNaHCO₃ solution and saturated NaCl solution. The organic layer was driedover Na₂SO₄, filtered and concentrated under reduced pressure. The crudeproduct was purified by flash chromatography (0%-100% EtOAc in hexanes)and EuK-IPPA.3OtBu (9) was isolated as a clear oil (163 mg, 71%). ¹H NMR(500 MHz, DMSO) δ 7.83 (m, 1H), 7.61 (d, 2H, J=8.0 Hz), 7.00 (d, 2H,J=7.9 Hz), 6.29 (d, 2H, J=6.5 Hz)), 6.20 (d, 2H, J=6.4 Hz), 4.04 (m,1H), 3.93 (m, 1H), 2.98 (m, 2H), 2.73 (t, 2H, J=8.2 Hz), 2.31 (t, 2H,J=8.0 Hz), 2.19 (m, 2H), 1.85 (m, 1H), 1.64 (m, 1H), 1.58 (m, 1H), 1.48(m, 1H), 1.37 (s, 27H), 1.32 (m, 2H), 1.21 (m, 2H). ESI(+)=746.1 [M+H]⁺.Calculated mass: 745.3

EuK-IPPA.3OtBu (9) (50 mg, 67 μmol) was dissolved in CH₂Cl₂ (3 mL) andTFA (3 mL) and stirred at rt under Ar for 3 h. The solvent was removedunder a stream of N₂ and the crude product was purified by prep HPLC.The peak corresponding to the product was collected and lyophilized, andRPS-026 was isolated as a white solid residue (15.5 mg, 40%). ¹H NMR(500 MHz, DMSO) δ 7.80 (m, 1H), 7.61 (d, 2H, J=7.9 Hz), 7.01 (d, 2H,J=8.0 Hz), 6.31 (m, 2H), 4.12 (m, 1H), 4.05 (m, 1H), 2.96 (m, 2H), 2.74(t, 2H, J=8.1 Hz), 2.32 (t, 2H, J=8.0 Hz), 2.21 (m, 2H), 1.86 (m, 1H),1.70 (m, 1H), 1.64 (m, 1H), 1.47 (m, 1H), 1.32 (m, 2H), 1.21 (m, 2H).ESI(+)=578.0 [M+H]⁺. Calculated mass: 577.1

(((S)-1-Carboxy-5-(2-(4-iodophenyl)acetamido)pentyl)carbamoyl)-L-glutamicacid (RPS-027)

To a solution of 2-(p-iodophenyl)acetic acid (81 mg, 0.308 mmol), HOAt(0.6M in THF, 0.51 mL, 0.308 mmol) and HATU (175 mg, 0.461 mmol) in DMF(1 mL) cooled to 0° C. under Ar was added a solution of EuK.3OtBu (1)(150 mg, 0.308 mmol) in DMF (1 mL). The mixture was stirred for 10 min,then (0.107 mL, 0.615 mmol) DIPEA was added. The reaction was stirredfor 20 min at 0° C., and then for a further 3 h while warming to rt. Themixture was diluted with EtOAC (25 mL) and washed with 1N HCl, saturatedNaHCO₃ solution and saturated NaCl solution. The organic layer was driedover Na₂SO₄, filtered and concentrated under reduced pressure. The crudeproduct was purified by flash chromatography (0%-100% EtOAc in hexanes)and EuK-IPPA.3OtBu (10) was isolated as a yellow oil (167 mg, 74%). ¹HNMR (500 MHz, CDCl₃) δ 7.51 (d, 2H, J=8.4 Hz), 7.09 (br s, 1H), 6.98 (d,2H, J=8.4 Hz), 6.00 (d, 1H, J=8.4 Hz), 5.70 (d, 1H, J=7.9 Hz), 4.25 (m,1H), 4.10 (m, 1H), 3.41 (d, 2H, J=5.4 Hz), 3.13-3.07 (m, 2H), 2.23 (m,2H), 1.97 (m, 1H), 1.76 (m, 1H), 1.61 (m, 1H), 1.41-1.23 (m, 3H), 1.37(s, 9H), 1.33 (s, 18H), 1.21 (m, 2H). ESI(+)=722.4 [M+H]⁺. Calculatedmass: 721.3

EuK-IPAA.3OtBu (10) (114 mg, 159 μmol) was dissolved in CH₂Cl₂ (0.5 mL)and TFA (0.5 mL) and stirred at rt under Ar for 5 h. The solvent wasremoved under a stream of N₂ and the crude product was purified by prepHPLC. The peak corresponding to the product was collected andlyophilized, and RPS-027 was isolated as a white solid residue (85 mg,95%). ¹H NMR (500 MHz, DMSO) δ 12.44 (br s, 3H), 8.05 (t, 1H, J=5.5 Hz),7.66 (d, 2H, J=8.4 Hz), 7.07 (d, 2H, J=8.4 Hz), 6.35 (d, 1H, J=8.3 Hz),6.31 (d, 1H, J=8.3 Hz), 4.14-4.05 (m, 2H), 3.36 (s, 2H), 3.03 (m, 2H),2.33-2.21 (m, 2H), 1.95 (m, 1H), 1.63-1.57 (m, 2H), 1.49 (m, 1H), 1.41(m, 2H), 1.30 (m, 2H). ESI(+)=563.9 [M+H]+; 561.9 [M−H]⁻. Calculatedmass: 563.1

Di-tert-butyl(((S)-1-(tert-butoxy)-1-oxo-6-(4-(4-(trimethylstannyl)phenyl)butanamido)hexan-2-yl)carbamoyl)-L-glutamate(11)

To a solution of EuK-IPBA.3OtBu (4) (86 mg, 113 μmol) in dioxane (20 mL)was added (SnMe₃)₂ (92.7 mg, 283 μmol) and PdCl₂(PPh₃)₂ (8 mg, 11.3μmol), and the mixture was heated to 80° C. under Ar for 90 min. Then itwas cooled to room temperature and the solvent was removed under reducedpressure. The crude residue was dissolved in CH₂Cl₂ (25 mL) and filteredthrough celite. The filtrate was concentrated under reduced pressure andthe crude residue was purified by flash chromatography (0%-100% EtOAc inhexanes). The product EuK-IPBA.SnMe₃ (11) was isolated as a clear oilthat solidified upon standing (18 mg; 20%). ¹H NMR (500 MHz, DMSO) δ7.75 (m, 1H), 7.34 (d, 2H, J=7.4 Hz), 7.13 (d, 2H, J=7.6 Hz), 6.27 (m,2H), 4.03 (m, 1H), 3.95 (m, 1H), 3.00 (m, 2H), 2.52 (2H), 2.22 (m, 2H),2.04 (t, 2H, J=7.4 Hz), 1.85 (m, 1H), 1.76 (quint, 2H, J=7.4 Hz), 1.67(m, 1H), 1.58 (m, 1H), 1.50 (m, 1H), 1.38 (s, 27H), 1.32 (m, 2H), 1.26(m, 2H), 0.24 (s, 9H). ESI(+)=798.1 (100%), 796.2 (75%), 794.2 (45%)[M+H]⁺. Calculated mass: 797.4 (100%), 795.4 (74.3%), 793.4 (44.6%).

Di-tert-butyl(((S)-1-(tert-butoxy)-1-oxo-5-(4-(4-(trimethylstannyl)phenyl)butanamido)pentan-2-yl)carbamoyl)-L-glutamate(12)

To a solution of EuO-IPBA.3OtBu (5) (74 mg, 9.9 μmol) in dioxane (3 mL)was added (SnMe₃)₂ (52 μL, 25.0 μmol) and PdCl₂(PPh₃)₂ (7 mg, 10.0μmol), and the resulting mixture was heated to 80° C. under Ar for 90min. The reaction was then cooled to rt and the solvent was concentratedunder reduced pressure. The crude residue was dissolved in CH₂Cl₂ (20mL) and filtered through celite. The filtrate was concentrated underreduced pressure to give a brown oil. The oil was purified by silicachromatography (50%-90% EtOAc in hexanes) and a colorless oil wasisolated from which a white solid precipitated. The oil was re-dissolvedin CH₂Cl₂, filtered and concentrated under reduced pressure to giveEuO-IPBA.SnMe₃ (12) as a colorless oil (29 mg, 37%). ¹H NMR (500 MHz,DMSO) δ 7.80 9m, 1H), 7.37 (d, 2H, J=7.9 Hz), 7.14 (d, 2H, J=8.1 Hz),6.32 (d, 1H, J=7.6 Hz), 6.24 (d, 1H, J=7.6 Hz), 4.03 (m, 1H), 3.96 (m,1H), 3.03 (m, 2H), 2.52 (m, 2H), 2.18 (m, 2H), 2.07 (t, 2H, J=8.0 Hz),1.86 (m, 1H), 1.77 (m, 2H), 1.66 (m, 1H), 1.59 (m, 1H), 1.50 (m, 1H),1.38 (s, 9H), 1.32 (m, 2H), 0.24 (s, 9H). ESI(+)=784.4 (100%), 782.4(70%), 780.3 (40%) [M+H]⁺. Calculated mass: 783.4 (100%), 781.4 (74.3%),779.4 (44.6%)

Di-tert-butyl(((S)-(1-tert-butoxy)-1-oxo-5-(3-(4-(trimethylstannyl)phenyl)propanamido)pentan-2-yl)carbamoyl)-L-glutamate(13)

To a solution of EuO-IPPA.3OtBu (6) (38 mg, 52 μmol) in dioxane (3 mL)was added (SnMe₃)₂ (43 mg, 130 μmol) and PdCl₂(PPh₃)₂ (3.7 mg, 5.2μmol), and the reaction was heated to 80° C. for 100 min under Ar. Thereaction was then cooled to rt and the solvent removed under reducedpressure. The crude residue was dissolved in CH₂Cl₂ (12 mL) and filteredthrough celite.

The filtrate was concentrated under reduced pressure to give a brownoil. The oil was purified by silica chromatography (50% EtOAc inhexanes) to give EuO-IPPA. SnMe₃ (13) as a colorless oil that solidifiedupon standing (15 mg; 38%). ¹H NMR (500 MHz, CDCl₃) δ 7.41 (d, 2H, J=7.9Hz), 7.20 (dd, 2H, J₁=12.8 Hz, J₂=4.9 Hz), 6.24 (t, 1H, J=5.5 Hz), 5.27(d, 2H, J=8.1 Hz), 4.36-4.28 (m, 2H), 3.31 (m, 1H), 3.20 (m, 1H), 2.94(t, 2H, J=7.9 Hz), 2.48 (t, 2H, J=8.0 Hz), 2.25 (m, 2H), 2.08 (m, 1H),1.85 (m, 1H), 1.74 (m, 1H), 1.59-1.46 (m, 3H), 1.45 (s, 18H), 1.44 (s,9H), 0.27 (s, 9H). ESI(+)=770.3 (100%), 768.2 (75%), 766.4 (50%) [M+H]⁺.Calculated mass: 769.3 (100%), 767.3 (74.3%), 765.3 (44.6%)

Di-tert-butyl(((S)-1-tert-butoxy)-1-oxo-5-(2-(4-(trimethylstannyl)phenyl)acetamido)pentan-2-yl)carbamoyl)-L-glutamate(14)

EuO-IPAA.3OtBu (7) (22 mg, 31 μmol) was dissolved in dioxane (5 mL).(SnMe₃)₂ (16 μL, 77 μmol) and PdCl₂(PPh₃)₂ (2.2 mg, 5.1 μmol) were addedconsecutively and the reaction was heated to 80° C. for 3 h under Ar. Itwas then cooled to rt and filtered through celite. The celite was washedwith dioxane (6 mL) and CH₂Cl₂ (5 mL). The combined organic fractionswere concentrated under reduced pressure to give a pale oil. The oil waspurified by silica chromatography (0%-90% EtOAC in hexanes), and theproduct was collected and lyophilized to give EuO-IPAA.SnMe₃ (14) as awhite solid (8 mg; 35%). ¹H NMR (500 MHz, CDCl₃) δ 8.06 (t, 1H, J=5.7Hz), 7.39 (d, 2H, J=7.9 Hz), 7.21 (d, 2H, J=7.9 Hz), 6.31 (d, 1H, J=8.4Hz), 6.26 (d, 1H, J=8.3 Hz), 4.04 (m, 1H), 3.98 (m, 1H), 3.31 (s, 2H),3.02 (m, 2H), 2.29-2.19 (m, 3H), 1.87 (m, 1H), 1.67 (m, 1H), 1.63 (m,1H), 1.50 (m, 2H), 1.40 (s, 9H), 1.39 (s, 9H), 1.38 (s, 9H), 0.25 (s,9H). ESI(+)=756.2 (100%), 754.3 (70%), 752.4 (45%) [M+H]⁺. Calculatedmass: 755.3 (100%), 753.3 (74.3%), 751.3 (44.6%)

Tetra-tert-butyl(3S,7S,12S)-5,10,18-trioxo-21-(4-(trimethylstannyl)phenyl)-4,6,11,17-tetraazahenicosane-1,3,7,12-tetracarboxylate(15)

EuEKIPBA.4OtBu (8) (25 mg, 26 μmol) and PdCl₂(PPh₃)₂ (2.1 mg, 3.0 μmol)were dissolved in dioxane (3 mL) and stirred at rt under Ar. Then(SnMe₃)₂ (25 mg, 75 μmol) was added and the reaction was heated to 80°C. and stirred under Ar for 90 min. The reaction was then cooled to rtand concentrated under reduced pressure. The crude residue was dissolvedin CH₂Cl₂ (5 mL) and filtered through celite. The filtrate wasconcentrated and the residue was purified by silica chromatography(50%-100% EtOAc in hexanes), and EuEK-IPBA.SnMe₃ (15) was isolated as aclear oil (19 mg; 73%) that solidified upon standing at 0° C. ¹H NMR(500 MHz, CDCl₃) δ 7.40 (d, 2H, J=7.9 Hz), 7.23 (d, 1H, J=7.7 Hz), 7.16(dd, 2H, J₁=12.7 Hz, J₂=4.9 Hz), 5.90 (d, 1H, J=8.5 Hz), 5.75 (t, 1H,J=5.5 Hz), 5.25 (d, 1H, J=9.0 Hz), 4.46 (m, 1H), 4.36 (m, 1H), 4.23 (m,1H), 3.22 (m, 2H), 2.62 (t, 2H, J=7.6 Hz), 2.33 (t, 2H, J=7.8 Hz), 2.28(m, 1H), 2.20-2.15 (m, 5H), 2.04 (m, 1H), 2.00-1.91 (m, 3H), 1.73 (m,2H), 1.65 (m, 2H), 1.47 (s, 9H), 1.46 (s, 9H), 1.45 (s, 9H), 1.43 (s,9H), 1.40 (m, 2H), 0.27 (s, 9H). ESI(+)=983.8 (100%), 981.8 (75%), 984.9(50%) [M+H]⁺. Calculated mass: 982.5 (100%), 980.5 (74.3%) 983.5 (49.8%)

Di-tert-butyl(((S)-1-(tert-butoxy)-1-oxo-6-(3-(4-(trimethylstannyl)phenyl)propanamido)hexan-2-yl)carbamoyl)-L-glutamate(16)

To a solution of EuK-IPPA.3OtBu (9) (59 mg, 79 μmol) in dioxane (20 mL)was added (SnMe₃)₂ (65 mg, 198 μmol) and PdCl₂(PPh₃)₂ (5.6 mg, 7.9μmol), and the mixture was heated to 80° C. under Ar for 90 min. Then itwas cooled to room temperature and the solvent was removed under reducedpressure. The crude residue was dissolved in CH₂Cl₂ (25 mL) and filteredthrough celite. The filtrate was concentrated under reduced pressure andthe crude residue was purified by flash chromatography (0%-100% EtOAc inhexanes). The product EuK-IPPA. SnMe₃ (16) was isolated as a clear oilthat solidified upon standing (51 mg; 82%). ¹H NMR (500 MHz, DMSO) δ7.82 (m, 1H), 7.39 (d, 2H, J=8.0 Hz), 7.17 (d, 2H, J=8.1 Hz), 6.33 (d,1H, J=5.9 Hz), 6.27 (d, 1H, J=6.1 Hz), 4.06 (m, 1H), 3.97 (m, 1H), 3.04(m, 2H), 2.79 (t, 2H, J=7.7 Hz), 2.34 (t, 2H, J=7.8 Hz), 2.24 (m, 2H),1.89 (m, 1H), 1.69 (m, 1H), 1.58 (m, 1H), 1.52 (m, 1H), 1.41 (s, 27H),1.34 (m, 2H), 1.26 (m, 2H), 0.25 (s, 9H). (ESI(+)=784.2 (100%), 782.2(75%), 780.3 (45%) [M+H]⁺. Calculated mass: 783.4 (100%), 781.4 (74.3%),779.4 (44.6%).

Di-tert-butyl(((S)-1-(tert-butoxy)-1-oxo-6-(2-(4-(trimethylstannyl)phenyl)acetamido)hexan-2-yl)carbamoyl)-L-glutamate(17)

To a solution of EuK-IPAA.3OtBu (10) (70 mg, 96 μmol) in dioxane (20 mL)was added (SnMe₃)₂ (78 mg, 239 μmol) and PdCl₂(PPh₃)₂ (6.7 mg, 9.6μmol), and the mixture was heated to 80° C. under Ar for 90 min. Then itwas cooled to room temperature and the solvent was removed under reducedpressure. The crude residue was dissolved in CH₂Cl₂ (25 mL) and filteredthrough celite. The filtrate was concentrated under reduced pressure andthe crude residue was purified by flash chromatography (0%-100% EtOAc inhexanes). The product EuK-IPAA.SnMe₃ (17) was isolated as a clear oilthat solidified upon standing (50 mg; 69%). ¹H NMR (500 MHz, CDCl₃) δ7.41 (d, 2H, J=7.9 Hz), 7.23 (d, 2H, J=7.9 Hz), 6.39 (m, 1H), 5.70 (d,1H, J=8.3 Hz), 5.55 (d, 1H, J=7.9 Hz), 4.32 (m, 1H), 4.21 (m, 1H), 3.51(d, 2H, J=5.1 Hz), 3.21 (m, 1H), 3.10 (m, 1H), 2.22 (m, 2H), 2.02 (m,1H), 1.84 (m, 1H), 1.66 (m, 1H), 1.49 (m, 1H), 1.42 (m, 2H), 1.41 (s,9H), 1.40 (s, 9H), 1.39 (s, 9H), 1.30 (m, 2H), 0.24 (s, 9H).ESI(+)=770.1 (100%), 768.2 (75%), 766.0 (45%) [M+H]⁺. Calculated mass:769.3 (100%), 767.3 (74.3%), 765.3 (44.6%).

Radiosynthesis of Exemplary Compounds.

A representative synthetic scheme for certain exemplary compounds of thepresent technology is presented below in Scheme 2.

Radiolabeling was carried out according to a modified version of theprotocol described in Zechmann C M, Afshar-Oromieh A, Armor T, et al.Radiation dosimetry and first therapy results with a ¹²⁴I/¹³¹I-labeledsmall molecule (MIP-1095) targeting PSMA for prostate cancer therapy.Eur J Nucl Med Mol Imaging. 2014; 41:1280-1292, incorporated herein byreference. 100 μL of a 250 μg/mL solution of organnostannane precursor(e.g., any one of compounds 11-17) in EtOH was added to a vialcontaining 74-740 MBq (2-20 mCi) Na¹²⁴I or Na¹³¹I in 30-60 μL aqueousNaOH. A 15% v/v H₂O₂/AcOH solution was prepared and 50 μL wastransferred immediately to the reaction vial. The reaction was mixed for20s and let stand for 5 min at room temperature. It was then dilutedwith 3 mL H₂O and passed through a pre-activated SOLA™ cartridge (ThermoScientific). The cartridge was washed with H₂O (3 mL) and dried withair. The radiolabeled intermediate was eluted into a second vial with 1mL of a 4M HCl/dioxane solution. The reaction was mixed for 20s and letstand for 40 min. It was then diluted with H₂O (9 mL) and passed througha pre-activated Bond Elut Plexa™ cartridge (Agilent Technologies, Inc.).The cartridge was washed with 5 mL of a 20% v/v EtOH/H₂O solution anddried with air. The radiolabeled product was eluted with DMSO (100-300μL).

The radiochemical yield, radiochemical purity, and specific activity areprovided below in Table 1, where RCY=radiochemical yield,RCP=radiochemical purity, and S.A.=Specific activity.

TABLE 1 S.A. Compound RCY (%) RCP (%) (GBq/μmol)¹ ¹³¹I-RPS-001 71.8 >973.15 ¹³¹I-RPS-005 62.0 >96 3.52 ¹³¹I-RPS-020 66.7 >94 4.29 ¹³¹I-RPS-02253.6 >90 3.06 ¹³¹I-RPS-025 43.5 >93 2.02 ¹³¹I-RPS-027 49.5 >98 9.18¹Based on a starting activity of 72-370 MBq (2-10 mCi)Radiochemical yield ranged from 43-72% and radiochemical purity wasgreater than 90% for all compounds tested. For example, ¹³¹I-RPS-027 wasprepared in 49.5% radiochemical yield from its organostannane precursor.Specific activity varied from 2-10 GBq/4 mol according to the starting¹²⁴I or ¹³¹I activity. The deprotection step proved to be timesensitive: for reaction times below 40 minutes, incomplete deprotectionwas observed, while reaction times greater than 45 minutes led to theformation of an unidentified impurity that could not be removed duringpurification by solid phase extraction. No significant difference inlabeling yield was observed when ¹²⁴I was used in place of ¹³¹I. Thestructure for ¹³¹I-RPS-001 (alternately described herein as¹³¹I-MIP-1095) is provided below.

Representative Biological Assays

HSA Affinity Determination.

HSA was immobilized to HPLC-grade silica by the Schiff base method asdescribed previously and were packed into 10 mm×2.1 mm i.d.microcolumns. See Chen J, Hage D S. Quantitative studies of allostericeffects by biointeraction chromatography: analysis of protein bindingfor low-solubility drugs. Anal Chem. 2006:78:2672-2683 and Matsuda R,Anguizola J, Hoy K S, Hage D S. Analysis of drug-protein interactions byhigh-performance affinity chromatography: interactions of sulfonyl ureadrugs with normal and glycated human serum albumin. Methods Mol Biol.2015; 1286:255-277, each of which is incorporated herein by reference.The protein content of these columns was approximately 60 mg HSA pergram of silica. See Zheng X, Podariu M, Bi C, Hage DS. Development ofenhanced capacity affinity microcolumn by using a hybrid of proteincross-linking/modification and immobilization. J. Chromatogr A. 2015;1400:82-90, incorporated herein by reference. Control microcolumns wereprepared in the same manner but with no HSA being added during theimmobilization step. The retention factor for each compound was measuredon both an HSA microcolumn and a control column by injecting 5 μLsamples that contained approximately 50 μM of the compound in 0.067Mpotassium phosphate buffer (pH 7.4). All samples were injected intriplicate at room temperature and at 1.0 mL/min, with the phosphatebuffer used as the mobile phase. Similar injections were made withsamples containing sodium nitrate, which was used as a void volumemarker. Elution of the injected compounds was monitored by absorbancedetection. The dissociation constant (Kd) for each compound with HSAestimated by using the measured retention factors, after correcting forany observed retention on the control column, along with the estimatedcontent of active HSA in the column, as based on injections made withwarfarin and L-tryptophan (i.e., probes for Sudlow sites I and II ofHSA). See Chen J, Hage D S. Anal Chem. 2006:78:2672-2683 (cited above)and Joseph K S, Hage DS. The effects of glycation on the binding ofhuman serum albumin to warfarin and L-tryptophan. J Pharm Biomed Anal.2010; 53:811-818, incorporated herein by reference. The estimatedprecision of the Kd values was ±2-14%.

Cell Culture.

The PSMA-expressing human prostate cancer cell line, LNCaP, was obtainedfrom the American Type Culture Collection. Cell culture supplies werefrom Invitrogen unless otherwise noted. LNCaP cells were maintained inRPMI-1640 medium supplemented with 10% fetal bovine serum (Hyclone), 4mM L-glutamine, 1 mM sodium pyruvate, 10 mMN-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid (HEPES), 2.5 mg/mLD-glucose, and 50 μg/mL gentamicin in a humidified incubator at 37°C./5% CO₂. Cells were removed from flasks for passage or for transfer to12-well assay plates by incubating them with 0.25%trypsin/ethylenediaminetetraacetic acid (EDTA).

In Vitro Determination of IC₅₀.

IC₅₀ values of the non-radioactive iodine-containing ligands weredetermined by screening in a multi-concentration competitive bindingassay against^(99m)Tc-((7S,12S,16S)-1-(1-(carboxymethyl)-1H-imidazol-2-yl)-2-((1-(carboxymethyl)-1H-imidazol-2-yl)methyl)-9,14-dioxo-2,8,13,15-tetraazaoctadecane-7,12,16,18-tetracarboxylicacid technetium tricarbonyl complex) (^(99m)Tc-MIP-1427) for binding toPSMA on LNCaP cells, according to protocols described in Kelly J,Amor-Coarasa A, Nikolopoulou A, et al. Synthesis and pre-clinicalevaluation of a new class of high-affinity ¹⁸F-labeled PSMA ligands fordetection of prostate cancer by PET imaging. Eur J Nucl Med Mol Imaging.2017; 44, 647-661, incorporated herein by reference. Briefly, LNCaPcells were plated 48 h prior to the experiment to achieve a density ofapproximately 5×10⁵ cells/well (in triplicate) in RPMI-1640 mediumsupplemented with 0.25% bovine serum albumin. The cells were incubatedfor 1 h with 1 nM ^(99m)Tc-MIP-1427 in serum-free RPMI-1640 medium inthe presence of 0.1-10,000 nM test compounds. Radioactive incubationmedia was then removed by pipette and the cells were washed twice using1 mL ice-cold HEPES buffer. Cells were harvested from the plates andtransferred to tubes for radioactive counting using a Packard Cobra IIGamma Counter. IC₅₀ values were determined by non-linear regressionusing GraphPad Prism software.

Inoculation of Mice with Xenografts.

All animal studies were approved by the Institutional Animal Care andUse Committee of Weill Cornell Medicine and were undertaken inaccordance with the guidelines set forth by the USPHS Policy on HumaneCare and Use of Laboratory Animals. Animals were housed under standardconditions in approved facilities with 12 h light/dark cycles. Food andwater was provided ad libitum throughout the course of the studies. Maleinbred athymic nu/nu mice were purchased from The Jackson Laboratory.For inoculation in mice, LNCaP cells were suspended at 4×10⁷ cells/mL ina 1:1 mixture of PBS:Matrigel (BD Biosciences). Each mouse was injectedin the left flank with 0.25 mL of the cell suspension. The mice wereimaged when the tumors reached approximately 200-400 mm³, whilebiodistributions were conducted when tumors were in the range 100-400mm³.

Tissue Distribution Studies.

A quantitative analysis of the tissue distribution of ¹³¹I-labeledcompounds was performed in separate groups of male NCr-nu/nu micebearing LNCaP cell xenografts administered via the tail vein as a bolusinjection (approximately 370 kBq (10 μCi)/mouse) in a volume of 0.05-0.1mL of saline solution containing 2.5% v/v DMSO. The animals (n=3-5/timepoint) were euthanized by asphyxiation with CO₂ at the indicated timepoints after injection. Tissues, including blood, heart, lungs, liver,spleen, pancreas, kidneys, stomach, large and small intestines (withcontents), skeletal muscle, bone, and tumor, were dissected, excised,weighed wet (Sartorius analytical balance), and counted in a Wizardautomated γ-counter (Perkin Elmer). A 1% ID/g standard was counted withthe tissue samples. Tissue time-radioactivity levels expressed aspercent injected dose per gram of tissue (% ID/g) were determined. Bloodpharmacokinetics were modeled as a dual compartment system usingbi-exponential least-squares regression fit to the data. Regressionmethod was implemented in MATLAB R2015b (MathWorks, Natick, Mass.).

Imaging Studies.

LNCaP xenograft tumor-bearing mice (two per compound) were injectedintravenously via the tail vein as a bolus injection of 7.03-7.77 MBq(190-210 μCi) of ¹²⁴I-RPS-027. The specific activity of ¹²⁴I-RPS-027 wasin the range 3-10 GBq/μmol. The mice were imaged by μPET/CT (Inveon™;Siemens Medical Solutions, Inc.) at 1 h, 3 h, 6 h, 24 h and 48 hpost-injection. Total acquisition time was thirty minutes, and a CT scanwas obtained either immediately before or immediately after theacquisition for both anatomical co-registration and attenuationcorrection. The data were reconstructed using the commercial Inveon™software supplied by the vendor. Image-derived tumor uptake wasestimated by drawing a region of interest (ROI).

Representative Activity of Compounds of the Present Technology

Exemplary In Vitro Study Results.

Table 2 below provides the results of the affinity studies for certainexemplary compounds with PMSA and human serum albumin (“HSA”).

TABLE 2 Compound IC₅₀ for PSMA (nM) Kd for HSA (μM) RPS-001 0.3 19.2(MIP-1095) RPS-005 4  0.98 RPS-020 8  2.1 RPS-022 10 22.9 RPS-023 1053.2 RPS-025 15 <1*  RPS-026 40 26.6 RPS-027 15 11.2 *Note: RPS-025could not be eluted from the HSA affinity microcolumn, which preventedthe calculation of a precise KdThe range of affinities for PSMA was determined to be 4-40 nM, with themajority of the compounds clustered between 10 nM and 15 nM. In the sameassay, RPS-001 (also known as MIP-1095) was found to have an IC₅₀ of 0.3nM. Compounds bearing the p-(iodophenyl)butyric acid moiety were foundto have a high affinity (1-2 μM) for HSA. RPS-025 could not be elutedfrom the column, which prevented the calculation of a precise Kd.RPS-027 had a modest affinity of 1 μM, while RPS-001, RPS-022 andRPS-026 were in the range 19-2 μM. RPS-023 (Kd=53.2 μM) was determinedto have a relatively weak affinity.

Biodistribution and μPET/CT Imaging In Vivo.

The biodistribution studies of the six ligands demonstrated that albuminbinding affinity contributed markedly to the different pharmacokineticsobserved in mice. RPS-001 (Kd=20 μM for HSA) demonstrated relativelyrapid clearance from the blood (FIG. 1A). Initial kidney uptake was high(>100% ID/g) and from 24-96 h post injection, ¹³¹I-RPS-001 activity inthe kidney cleared from 65.24±22.61% ID/g at 24 h to 2.12±2.47% ID/g at96 h. Tumor uptake was high with gradual tumor washout observed overseveral days (19.81±6.16% ID/g at 24 h vs. 10.21±4.30% ID/g at 96 h)(FIG. 1A), such that tumor-to-kidney ratio increased with time. Low,PSMA-mediated uptake was observed at 24 h post injection in the largeintestine (2.35±1.26% ID/g) and the spleen (2.41±1.40% ID/g), andaccumulated activity was negligible in all tissues except for the tumorand kidney by 48 h post injection. The tissue uptake at earlier timepoints was extrapolated using previously reported data (37).

Accumulation of ¹³¹I-RPS-005 (Kd=0.89 μM for HSA) in the blood wasexceptionally high, and clearance was slow over the 96 h observationwindow (FIG. 1B). At 24 h post injection, blood activity was 21.35±3.99%ID/g, which decreased to 15.57±3.98% ID/g by 96 h. This slow bloodclearance is likely to be responsible for the non-PSMA-mediated uptakeobserved in tissues such as the heart (4.40±0.74% ID/g at 24 h), lungs(8.87±0.74% ID/g at 24 h) and liver (3.41±0.56% ID/g at 24 h). Kidneyuptake (39.09±2.96% ID/g) was lower at 24 h post injection than observedfor ¹³¹I-RPS-001, but clearance was considerably slower. In combinationwith the comparatively low tumor uptake of approximately 10% (9.37±1.56%ID/g at 24 h; 10.82±2.64% ID/g at 96 h), these pharmacokinetics resultin poor tumor-to-background ratios at all time points.

As the tissue uptake of ¹³¹I-RPS-005 appeared to peak within the first24 h, ¹³¹I-RPS-020 (Kd=2.1 μM) was investigated at early time points aswell. Prolonged blood retention was also observed, with initialaccumulation of 16.20±4.68% ID/g at 1 h post injection only decreasingto 12.71±1.55% ID/g at 48 h (FIG. 2). This was associated with highoff-target uptake, most notably in the lungs (6.12±0.95% ID/g at 1 hpost injection) and kidneys (16.21±0.97% ID/g at 1 h). Activitycontinued to accumulate in the kidney, peaking at 22.26±2.48% ID/g at 24h post injection. Tumor uptake (4.81±1.27% ID/g) was lower than observedfor RPS-005, as a comparison of PSMA affinities might predict, but itremained stable over the course of the 48 h.

In contrast, ¹³¹I-RPS-022 (Kd=22.9 μM) showed rapid blood kinetics, withnegligible activity detected as early as 12 h post injection (FIG. 3).Considerable uptake was observed in the liver (12.46±1.63% ID/g) andsmall intestine (13.09±2.98% ID/g) at 1 h post injection, thoughclearance from each organ was rapid. Kidney uptake, which reached(52.18±5.35% ID/g) at 1 h post injection, had cleared to 2.27±1.41% ID/gby 24 h, leading to favorable tumor-to-kidney and tumor-to-backgroundratios at later time points. However, tumor uptake peaked at 7.20±0.10%ID/g at 1 h post injection and subsequently decreased to 3.35±1.70% ID/gby 6 h.

¹³¹I-RPS-027 showed a promising biodistribution profile over the timeperiod studied (FIG. 4). Activity in the blood at 1 h post injection was3.91±0.48% ID/g, which decreased to 0.58±0.17% ID/g by 24 h. Initialuptake was also observed in the liver (6.79±0.70% ID/g; 1 h), smallintestine (8.01±0.78% ID/g; 1 h), large intestine (8.56±1.67% ID/g; 3h), spleen (4.13±1.37% ID/g; 1 h) and heart (1.30±0.04% ID/g; 1 h).Clearance from these tissues decreased largely in proportion to bloodclearance, suggesting that the normal organ activity is related to bloodpool activity rather than tissue uptake. Minimal activity was detectedin the tissue by 12 h post injection with the exception of the kidney(15.12±2.82% ID/g) and the tumor (9.73±1.01% ID/g). Although maximumtumor uptake (12.41±0.84% ID/g; 3 h) was lower than for ¹³¹I-RPS-001,tumor uptake remained as high as 8.13±2.03% ID/g at 24 h and 3.05±1.30%ID/g at 72 h, leading to excellent tumor-to-background andtumor-to-kidney (>2) ratios as early as 18 h post injection. While tumoruptake of ¹³¹I-RPS-027 was roughly 50% of that for ¹³¹I-RPS-001 at alltime points studied, the kidney concentration of ¹³¹I-RPS-027 wasfivefold less than that for ¹³¹I-RPS-001.

Desirable pharmacokinetics continued to be observed at longer timepoints for ¹³¹I-RPS-027 (FIG. 4). Activity in the blood remaineddetectable up to 48 h post injection (0.20±0.06% ID/g), whiletumor-to-background ratio continued to increase due to rapid clearancefrom the kidney (1.04±0.65% ID/g at 48 h). These in vivo findings werevisually recapitulated by PET/CT imaging of LNCaP xenograft mice using¹²⁴I-RPS-027. Initial uptake in the tumor, kidneys and hepatobiliarysystem is evident at 1 h (FIG. 5), with clearance from non-target tissueresulting in highly specific tumor targeting at 24 h and 48 h postinjection.

Time-activity curves were plotted to facilitate a greater understandingof the pharmacokinetic profile of the dual binding ligands. Uptake inthe tumor, the blood and the kidneys is plotted in FIGS. 6A-6C. Thehighest tumor uptake is observed for ¹³¹I-RPS-001, and the kinetics oftumor washout are similar for the three compounds with lower affinityfor albumin (FIG. 6A). The level of activity in the tumor remains moststeady in the two ligands with highest albumin binding (FIG. 6A).Striking differences are apparent in the rate of blood clearance amongthe various compounds studied, with ¹³¹I-RPS-005 and ¹³¹I-RPS-020, bothhaving high affinity for albumin, showing minimal blood clearance over48 h and beyond (FIG. 6B). The clearance kinetics of ¹³¹I-RPS-001,¹³¹I-RPS-022 and ¹³¹I-RPS-027 reflect their relative affinities foralbumin, with ¹³¹I-RPS-022 clearing most quickly and ¹³¹I-RPS-027clearing most gradually. Blood curves show a rapid initial distributionphase followed by a slower elimination phase. In this model, t_(1/2) forthe distribution phase was 2.17 h, 2.1 h and 3.15 h for ¹³¹I-RPS-001,¹³¹I-RPS-022 and ¹³¹I-RPS-027, respectively, while the correspondingt_(1/2) for the elimination phase was 20.38 h, 17.3 h and 21.66 h. Incomparison, the half-lives for distribution and elimination phases for¹³¹I-RPS-020 were 3.85 h and 3,300 h, respectively.

Absolute kidney uptake of RPS-027 and RPS-022 was dramatically reducedcompared with RPS-001 at all time points studied. Kidney clearance isapproximately described by an exponential decay function for¹³¹I-RPS-001, ¹³¹I-RPS-022 and ¹³¹I-RPS-027 (FIG. 6C). In contrast,¹³¹I-RPS-005 and ¹³¹I-020 show prolonged retention and much flatterclearance curves. Tumor-to-kidney (T/K) and tumor-to-blood (T/B) ratioswere calculated as a function of time. The T/K ratio of ¹³¹I-RPS-027reaches approximately 3 by 24 h and continues to increase with time(FIG. 7A). In comparison, the T/K ratio of ¹³¹I-RPS-001 does not reach 3until nearly 96 h post injection. The T/K ratio of ¹³¹I-RPS-022 alsoincreases rapidly, particularly at earlier time points (>1 at 12 h postinjection), but this is driven more by rapid kidney clearance than bytumor uptake. The tumor-to-blood ratio of ¹³¹I-RPS-027 is lower than¹³¹I-RPS-001 (FIG. 7B), predominantly reflecting enhanced albuminbinding.

In comparison to ¹³¹I-MIP-1095, ¹³¹I-DCIBzL, and ²¹¹At-6, ¹³¹I-RPS-027shows considerably lower kidney uptake at all time points from 1 h to 72h post injection. See Hillier S, Rubino K, Maresca K, et al.[¹³¹I]MIP-1466, a small molecule prostate-specific membrane antigen(PSMA) inhibitor for targeted radiotherapy of prostate cancer (PCa). JNucl Med. 2012; 53(Suppl 1):170, Chen Y, Foss C A, Byun Y, et al.Radiohalogenated prostate-specific membrane antigen (PSMA)-based ureasas imaging agents for prostate cancer. J Med Chem. 2008; 51:7933-7943,and Kiess A P, Minn I, Vaidyanathan G, et al.(2S)-2-(3-(1-Carboxy-5-(4-[211At]astatobenzamido)pentyl)ureido)-pentanedioicacid for PSMA-targeted α-particle radiopharmaceutical therapy. J NuclMed. 2016; 57:1569-1575 (each of which is incorporated herein byreference) for ¹³¹I-MIP-1095, ¹³¹I-DCIBzL, and ²¹¹At-6, respectively.

The difference in uptake between ¹³¹I-MIP-1095 (alternately describedherein as ¹³¹I-RPS-001) and ¹³¹I-RPS-027 at 24 h is 20-fold. In thecontext of the dosimetry reported for MIP-1095 in patients, the lowerkidney uptake of ¹³¹I-RPS-027 projects to a significantly lower absorbeddose to the kidney, and a reduced risk of relevant nephrotoxicity attherapeutic doses or under a multiple treatment cycle regime. Moreover,the tumor-to-kidney ratio for ¹³¹I-RPS-027 is greater than 2 as soon as18 h post injection, rises to 3 by 24 h and exceeds 7 by 72 h. Thiscompares favorably to ²¹¹At-6, and a projection of the comparisonbetween ¹³¹I-DCIBzL and ²¹¹At-6 to RPS-027 predicts that astatinationwill further increase the ratio. As such, the dose-limiting,irreversible nephrotoxicity of ²¹¹At-6 is expected to be resolved by²¹¹At-RPS-027.

While certain embodiments have been illustrated and described, a personwith ordinary skill in the art, after reading the foregoingspecification, can effect changes, substitutions of equivalents andother types of alterations to the compounds of the present technology orsalts, pharmaceutical compositions, derivatives, prodrugs, metabolites,tautomers or racemic mixtures thereof as set forth herein. Each aspectand embodiment described above can also have included or incorporatedtherewith such variations or aspects as disclosed in regard to any orall of the other aspects and embodiments.

The present technology is also not to be limited in terms of theparticular aspects described herein, which are intended as singleillustrations of individual aspects of the present technology. Manymodifications and variations of this present technology can be madewithout departing from its spirit and scope, as will be apparent tothose skilled in the art. Functionally equivalent methods within thescope of the present technology, in addition to those enumerated herein,will be apparent to those skilled in the art from the foregoingdescriptions. Such modifications and variations are intended to fallwithin the scope of the appended claims. It is to be understood thatthis present technology is not limited to particular methods, reagents,compounds, compositions, labeled compounds or biological systems, whichcan, of course, vary. It is also to be understood that the terminologyused herein is for the purpose of describing particular aspects only,and is not intended to be limiting. Thus, it is intended that thespecification be considered as exemplary only with the breadth, scopeand spirit of the present technology indicated only by the appendedclaims, definitions therein and any equivalents thereof.

The embodiments, illustratively described herein may suitably bepracticed in the absence of any element or elements, limitation orlimitations, not specifically disclosed herein. Thus, for example, theterms “comprising,” “including,” “containing,” etc. shall be readexpansively and without limitation. Additionally, the terms andexpressions employed herein have been used as terms of description andnot of limitation, and there is no intention in the use of such termsand expressions of excluding any equivalents of the features shown anddescribed or portions thereof, but it is recognized that variousmodifications are possible within the scope of the claimed technology.Additionally, the phrase “consisting essentially of” will be understoodto include those elements specifically recited and those additionalelements that do not materially affect the basic and novelcharacteristics of the claimed technology. The phrase “consisting of”excludes any element not specified.

In addition, where features or aspects of the disclosure are describedin terms of Markush groups, those skilled in the art will recognize thatthe disclosure is also thereby described in terms of any individualmember or subgroup of members of the Markush group. Each of the narrowerspecies and subgeneric groupings falling within the generic disclosurealso form part of the invention. This includes the generic descriptionof the invention with a proviso or negative limitation removing anysubject matter from the genus, regardless of whether or not the excisedmaterial is specifically recited herein.

As will be understood by one skilled in the art, for any and allpurposes, particularly in terms of providing a written description, allranges disclosed herein also encompass any and all possible subrangesand combinations of subranges thereof. Any listed range can be easilyrecognized as sufficiently describing and enabling the same range beingbroken down into at least equal halves, thirds, quarters, fifths,tenths, etc. As a non-limiting example, each range discussed herein canbe readily broken down into a lower third, middle third and upper third,etc. As will also be understood by one skilled in the art all languagesuch as “up to,” “at least,” “greater than,” “less than,” and the like,include the number recited and refer to ranges which can be subsequentlybroken down into subranges as discussed above. Finally, as will beunderstood by one skilled in the art, a range includes each individualmember.

All publications, patent applications, issued patents, and otherdocuments (for example, journals, articles and/or textbooks) referred toin this specification are herein incorporated by reference as if eachindividual publication, patent application, issued patent, or otherdocument was specifically and individually indicated to be incorporatedby reference in its entirety. Definitions that are contained in textincorporated by reference are excluded to the extent that theycontradict definitions in this disclosure.

The present technology may include, but is not limited to, the featuresand combinations of features recited in the following letteredparagraphs, it being understood that the following paragraphs should notbe interpreted as limiting the scope of the claims as appended hereto ormandating that all such features must necessarily be included in suchclaims:

-   A. A compound of Formula I

or a pharmaceutically acceptable salt thereof, wherein

-   -   X¹ is 124I, 125I 127I 131I 211At, or Sn(R⁴)₃;    -   R¹, R², and R³ are each independently H, methyl, benzyl,        4-methoxybenzyl, or tert-butyl;    -   R⁴ is independently at each occurrence an alkyl group;    -   n is 1 or 2; and    -   m is 0, 1, 2, or 3.

-   B. The compound of Paragraph A, wherein R¹, R², and R³ are each    independently H or tert-butyl.

-   C. The compound of Paragraph A or Paragraph B, wherein R⁴ is    independently at each occurrence methyl, ethyl, propyl, propyl, or    butyl.

-   D. The compound of any one of Paragraphs A-C, wherein when n is 2,    then m is not 2.

-   E. The compound of any one of Paragraphs A-D, wherein the compound    of Formula I is a compound of Formula Ia

or a pharmaceutically acceptable salt thereof.

-   F. The compound of any one of Paragraphs A-E, wherein X¹ is ¹²⁴I,    ¹²⁵I, ¹³¹I, or ²¹¹At.-   G. A composition comprising a compound of any one of Paragraphs A-F    and a pharmaceutically acceptable carrier.-   H. A pharmaceutical composition for treating cancer expressing PSMA,    the composition comprising an effective amount of the compound    Paragraph F, wherein the effective amount is an amount effective for    treating the cancer.-   I. The pharmaceutical composition of Paragraph H, wherein the cancer    is glioma, cervical carcinoma, vulvar carcinoma, endometrial    carcinoma, primary ovarian carcinoma, metastatic ovarian carcinoma,    non-small cell lung cancer, small cell lung cancer, bladder cancer,    colon cancer, primary, gastric adenocarcinoma, primary colorectal    adenocarcinoma, renal cell carcinoma, or prostate cancer (such as    castration resistant prostate cancer).-   J. A method comprising administering a compound of Paragraph F to a    subject suffering from a cancer expressing PSMA.-   K. The method of Paragraph J, wherein the method comprises    administering an effective amount of the compound to the subject.-   L. The method of Paragraph J or Paragraph K, wherein the cancer is    glioma, cervical carcinoma, vulvar carcinoma, endometrial carcinoma,    primary ovarian carcinoma, metastatic ovarian carcinoma, non-small    cell lung cancer, small cell lung cancer, bladder cancer, colon    cancer, primary, gastric adenocarcinoma, primary colorectal    adenocarcinoma, renal cell carcinoma, or prostate cancer (such as    castration resistant prostate cancer).-   M. The method of any one of Paragraphs J-L, wherein administering    the compound comprises parenteral administration, preferably    intravenous administration.-   N. A compound of Formula II

or a pharmaceutically acceptable salt thereof, wherein

-   -   X₂ is ¹²⁴I, ¹²⁵I, ¹²⁷I, ¹³¹I, ²¹¹At, or Sn(R⁸)₃;    -   R⁵, R⁶, and R⁷ are each independently H, methyl, benzyl,        4-methoxybenzyl, or tert-butyl;    -   R⁸ is independently at each occurrence an alkyl group;    -   W¹ is a bond or —NH-alkylene-; and    -   p is 0, 1, 2, or 3.

-   O. The compound of Paragraph N, wherein R⁵, R⁶, and R⁷ are each    independently H or tert-butyl.

-   P. The compound of Paragraph N or Paragraph O, wherein R⁸ is    independently at each occurrence methyl, ethyl, propyl, propyl, or    butyl.

-   Q. The compound of any one of Paragraphs N-P, wherein the compound    of Formula II is a compound of Formula IIa

-   -   or a pharmaceutically acceptable salt thereof.

-   R. The compound of any one of Paragraphs N-Q, wherein X¹ is ¹²⁴I,    ¹²⁵I, ¹³¹I, or ²¹¹At.

-   S. A composition comprising a compound of any one of Paragraphs N-R    and a pharmaceutically acceptable carrier.

-   T. A pharmaceutical composition for treating cancer expressing PSMA,    the composition comprising an effective amount of the compound of    Paragraph R and a pharmaceutically acceptable excipient, wherein the    effective amount is an amount effective for treating the cancer.

-   U. The pharmaceutical composition of Paragraph T, wherein the cancer    is glioma, cervical carcinoma, vulvar carcinoma, endometrial    carcinoma, primary ovarian carcinoma, metastatic ovarian carcinoma,    non-small cell lung cancer, small cell lung cancer, bladder cancer,    colon cancer, primary, gastric adenocarcinoma, primary colorectal    adenocarcinoma, renal cell carcinoma, or prostate cancer (such as    castration resistant prostate cancer).

-   V. A method comprising administering a compound of Paragraph R to a    subject suffering from cancer expressing PSMA.

-   W. The method of Paragraph V, wherein the method comprises    administering an effective amount of the compound to the subject.

-   X. The method of Paragraph V or Paragraph W, wherein the cancer is    glioma, cervical carcinoma, vulvar carcinoma, endometrial carcinoma,    primary ovarian carcinoma, metastatic ovarian carcinoma, non-small    cell lung cancer, small cell lung cancer, bladder cancer, colon    cancer, primary, gastric adenocarcinoma, primary colorectal    adenocarcinoma, renal cell carcinoma, or prostate cancer (such as    castration resistant prostate cancer).

-   Y. The method of any one of Paragraphs V-X, wherein administering    the compound comprises parenteral administration, preferably    intravenous administration.

-   Z. A method of enhancing uptake of a therapeutic agent to a tumor    presenting prostate specific membrane antigen (“PSMA”), the method    comprising    -   administering a first therapeutic agent comprising a PMSA        targeting moiety and a human serum albumin binding moiety to a        subject with one or more cancer tumors, where the human serum        albumin binding moiety includes a radionuclide;    -   detecting distribution of the first therapeutic agent in the        subject; and    -   modifying the human serum albumin binding moiety of the first        therapeutic agent to provide a second therapeutic agent.

-   AA. The method of Paragraph Z, wherein the PMSA-targeting moiety    comprises a glutamate-urea-glutamate moiety or a    glutamate-urea-lysine moiety.

-   AB. The method of Paragraph Z or Paragraph AA, wherein the cancer is    glioma, cervical carcinoma, vulvar carcinoma, endometrial carcinoma,    primary ovarian carcinoma, metastatic ovarian carcinoma, non-small    cell lung cancer, small cell lung cancer, bladder cancer, colon    cancer, primary, gastric adenocarcinoma, primary colorectal    adenocarcinoma, renal cell carcinoma, or prostate cancer (such as    castration resistant prostate cancer).

-   AC. The method of any one of Paragraphs Z-AB, wherein the human    serum albumin binding moiety includes a ¹²⁴I-substituted, a    ¹²⁵I-substituted, a ¹³¹I-substituted, or ²¹¹At-substituted phenyl    moiety.

-   AD. The method of any one of Paragraphs Z-AC, wherein the human    serum albumin binding moiety includes a 4-(¹²⁴I)-substituted, a    4-(¹²⁵I)-substituted, a 4-(¹³¹I)-substituted, or a    4-(²¹¹At)-substituted phenyl moiety.

-   AE. The method of any one of Paragraphs Z-AD, wherein modifying the    first therapeutic agent comprises lengthening or shortening a    hydrocarbon chain of the human serum albumin binding moiety.

-   AF. The method of any one of Paragraphs Z-AE, wherein administering    the first therapeutic agent comprises parenteral administration.

-   AG. The method of any one of Paragraphs Z-AF, wherein the method    further comprises    -   administering the second therapeutic agent to a subject with one        or more cancer tumors;    -   detecting distribution of the second therapeutic agent in the        subject.

-   AH. The method of Paragraph AG, wherein the second therapeutic agent    exhibits higher tumor uptake in comparison with non-tumor tissues of    the subject than the first therapeutic agent.

-   AI. The method of any one of Paragraphs Z-AH, wherein the modifying    the first therapeutic agent comprises conjugating a polyalkane    glycol, polyethylene amine (PEI), polyglycine, carbohydrate polymer,    amino acid polymer, polyvinyl pyrolidone, a fatty acid, a fatty acid    ester group, or a combination of any two or more thereof to the    human serum albumin binding moiety.

-   AJ. The method of Paragraph AI, wherein the conjugating step    comprises inserting a polyalkane glycol, polyethylene amine (PEI),    polyglycine, carbohydrate polymer, amino acid polymer, polyvinyl    pyrolidone, a fatty acid, a fatty acid ester group, or a combination    of any two or more thereof between the PSMA-targeting moiety and the    human serum albumin binding moiety.

-   AK. The method of Paragraph AI or Paragraph AJ, wherein the    conjugating step comprises conjugating a polyalkane glycol,    polyethylene amine (PEI), polyglycine, carbohydrate polymer, amino    acid polymer, polyvinyl pyrolidone, a fatty acid, a fatty acid ester    group, or a combination of any two or more thereof at a position on    the human serum albumin binding moiety that is distal to the    PSMA-targeting moiety.

Other embodiments are set forth in the following claims, along with thefull scope of equivalents to which such claims are entitled.

What is claimed is:
 1. A compound of Formula I

or a pharmaceutically acceptable salt thereof, wherein X¹ is ¹²⁴I, ¹²⁵I,¹²⁷I, ¹³¹I, ²¹¹At, or Sn(R⁴)₃; R¹, R², and R³ are each independently H,methyl, benzyl, 4-methoxybenzyl, or tert-butyl; R⁴ is independently ateach occurrence an alkyl group; n is 1 or 2; and m is 0, 1, 2, or
 3. 2.The compound of claim 1, wherein when n is 2, then m is not
 2. 3. Thecompound of claim 1, wherein X¹ is ¹²⁴I, ¹²⁵I, ¹³¹I, or ²¹¹At.
 4. Acomposition comprising a compound of claim 3 and a pharmaceuticallyacceptable carrier.
 5. A pharmaceutical composition for treating acancer expressing prostate specific membrane antigen (“PSMA”), thecomposition comprising an effective amount of the compound of claim 3and a pharmaceutically acceptable excipient.
 6. The pharmaceuticalcomposition of claim 5, wherein the cancer is glioma, cervicalcarcinoma, vulvar carcinoma, endometrial carcinoma, primary ovariancarcinoma, metastatic ovarian carcinoma, non-small cell lung cancer,small cell lung cancer, bladder cancer, colon cancer, primary, gastricadenocarcinoma, primary colorectal adenocarcinoma, renal cell carcinoma,or prostate cancer.
 7. A method comprising administering a compound ofclaim 3 to a subject suffering from a cancer expressing prostatespecific membrane antigen (“PSMA”).
 8. The method of claim 7, whereinthe method comprises administering an effective amount of the compoundto the subject.
 9. The method of claim 7, wherein the cancer is glioma,cervical carcinoma, vulvar carcinoma, endometrial carcinoma, primaryovarian carcinoma, metastatic ovarian carcinoma, non-small cell lungcancer, small cell lung cancer, bladder cancer, colon cancer, primary,gastric adenocarcinoma, primary colorectal adenocarcinoma, renal cellcarcinoma, or prostate cancer.
 10. A compound of Formula II

or a pharmaceutically acceptable salt thereof, wherein X² is ¹²⁴I, ¹²⁵I,¹²⁷I, ¹³¹I, ²¹¹At, or Sn(R⁸)₃; R⁵, R⁶, and R⁷ are each independently H,methyl, benzyl, 4-methoxybenzyl, or tert-butyl; R⁸ is independently ateach occurrence an alkyl group; W¹ is a bond or —NH-alkylene-; and p is0, 1, 2, or
 3. 11. The compound of claim 10, wherein X¹ is ¹²⁴I, ¹²⁵I¹³¹I, or ²¹¹At.
 12. A composition comprising a compound of claim 11 anda pharmaceutically acceptable carrier.
 13. A pharmaceutical compositionfor treating a cancer expressing prostate specific membrane antigen(“PSMA”), the composition comprising an effective amount of the compoundof claim 11 and a pharmaceutically acceptable excipient.
 14. Thepharmaceutical composition of claim 13, wherein the cancer is glioma,cervical carcinoma, vulvar carcinoma, endometrial carcinoma, primaryovarian carcinoma, metastatic ovarian carcinoma, non-small cell lungcancer, small cell lung cancer, bladder cancer, colon cancer, primary,gastric adenocarcinoma, primary colorectal adenocarcinoma, renal cellcarcinoma, or prostate cancer.
 15. A method comprising administering acompound of claim 11 to a subject suffering from a cancer expressingprostate specific membrane antigen (“PSMA”).
 16. The method of claim 15,wherein the method comprises administering an effective amount of thecompound to the subject.
 17. The method of claim 15, wherein the canceris glioma, cervical carcinoma, vulvar carcinoma, endometrial carcinoma,primary ovarian carcinoma, metastatic ovarian carcinoma, non-small celllung cancer, small cell lung cancer, bladder cancer, colon cancer,primary, gastric adenocarcinoma, primary colorectal adenocarcinoma,renal cell carcinoma, or prostate cancer.
 18. A method of enhancinguptake of a therapeutic agent to a tumor presenting prostate specificmembrane antigen (“PSMA”), the method comprising administering a firsttherapeutic agent comprising a PMSA targeting moiety and a human serumalbumin binding moiety to a subject with one or more cancer tumors,where the human serum albumin binding moiety includes a radionuclide;detecting distribution of the first therapeutic agent in the subject;and modifying the first therapeutic agent to provide a secondtherapeutic agent.
 19. The method of claim 18, wherein modifying thefirst therapeutic moiety comprises lengthening or shortening ahydrocarbon chain of the human serum albumin binding moiety.
 20. Themethod of claim 18, wherein the method further comprises administeringthe second therapeutic agent to a subject with one or more cancertumors; detecting distribution of the second therapeutic agent in thesubject.